We generally think of Hollywood triple-threats as entertainers who can sing, dance, and act. But what about quadruple-threats? Or quintuple threats? As far as they go, Carrie Brownstein – the actor-singer-guitarist-screenwriter-memoirist – stands pretty much alone.

The star, co-creator and co-writer of Portlandia, which returns for its eighth and final season on 18 January, can also be found in early seasons of Transparent, on stage with the revered indie-rock heroines of Sleater-Kinney, or in bookstores as the author of Hunger Makes Me a Modern Girl, a witty, bare-boned account of Brownstein’s coming-of-age in the punk-feminist enclaves of the Pacific north-west.

But for now, Brownstein, 43, is focused on promoting Portlandia, which she writes with her co-star Fred Armisen, a veteran of Saturday Night Live. The two won a Peabody Award for the series in 2011, when it was just one year young, and since then it’s grown to become one of television’s sharpest sketch comedies, mischievous and farcical in its satire of hipster culture in Portland, Oregon, where Brownstein has lived for more than a decade.

In the show, Brownstein and Armisen, among other characters, play the nosy proprietors of a feminist bookstore called Women & Women First; bandmates who use a cat as their on-stage prop; “missionaries” recruited by the mayor to go door-to-door in Seattle spreading “the gospel of Portland”; and, in the new season, true-crime podcasters meddling in the work of a chagrined local police department. That the two have yet to run out of ideas speaks to both the depth of their imaginations and the preponderance of self-parody to be mined in the world of microbreweries and tech startups.

“Because we’re not a nightly talkshow or a weekly summation of the news, like Full Frontal or John Oliver, we can’t necessarily do something that’s hyper-topical,” Brownstein says, reflecting on the zeitgeist-y nature of Portlandia’s satire. “Our most favorite trajectory is to examine phenomena through the lens of absurdism, but we try to infuse it with a sense of timelessness.”

Although it’s hard for Brownstein to believe the show is ending, it doesn’t necessarily feel like a closing of the book. “What’s nice about television at this stage is that it feels ongoing,” she says. “The lifespan of a television show is not as finite as it used to be because of streaming.”

Now that Portlandia is finished, though, Brownstein has the time to wear more of her many hats: her memoir is being developed as a TV series for Hulu, and she’s back in the studio working with her bandmates, Corin Tucker and Janet Weiss, on Sleater-Kinney’s ninth record. One imagines that working in so many different media requires a kind of rigorous compartmentalization, but for Brownstein, her talents coalesce rather naturally.

“It doesn’t feel schizophrenic or bifurcated in any way, because I think at the core of it is storytelling, whether it’s songwriting or memoir or essays or even Portlandia,” she says, noting that her collaborations with Armisen and Sleater-Kinney complement one another. “The process is obviously different, but the essence of the work is the same: it’s allowing for someone else’s vulnerability in the room; it’s a lot of listening; it’s not being too precious about your own ideas.”

Armisen, beloved by comedy buffs for his strange, offbeat humor, has been open about his misgivings with regard to his personal relationships, going so far as to say he “feels bad” for the women he’s dated (one of those women, his ex-wife Elisabeth Moss, calls their marriage “traumatizing”). The Portlandia duo once suggested that the richness of their collaborative kinship came at the expense of their individual romances but Brownstein, in retrospect, says that claim is “bullshit”.

“I think to downplay what it can mean to have a creative partnership with someone does a disservice to the uniqueness and intimacy of that dynamic,” she clarifies. “It all functions perfectly well. I feel like Fred is kind of Mr Nice Guy.”

In the 1990s, Sleater-Kinney was one of the most celebrated rock bands in America, emerging from Washington’s riot grrrl subculture with an aura of gritty, iconoclastic defiance. The band was third-wave before it was au courant; but now that the culture is gradually catching up with them, Brownstein is modest in discussing the trailblazer-status that’s been bestowed upon Sleater-Kinney.

“To me, we’re part of a much longer continuum that started well before the 1990s,” she says. “Anytime there’s people doing the real work to dismantle and investigate systems of oppression and exploitation, to have a conversation that’s intersectional, that’s very exciting. If you look backwards, it’s an accumulation of moments that hopefully add up to practical and institutional changes.”

In a 2012 New Yorker profile, Brownstein posited that Armisen, perhaps because he’s a man, and also because he didn’t get his start in the underground, found it easier to take pride in the pair’s accomplishments. Asked if that has changed at all, especially after a Peabody and four Emmy nominations, Brownstein says she’s lucky to have absorbed the perspectives of both her more anarchist origins and the mainstream.

“How comfortable one is taking credit for their work depends on the person. I think tall poppy syndrome is endemic to smaller creative communities, but I also really value the fairly anti-capitalist approach of the more radical artistic communities from which I came,” she says. “It reminds me to redefine ambition, because I think ambition has become kind of a dirty word. We always think of it as being part of a capitalist, hierarchical structure that subjugates people. But ambition doesn’t have to be anathema to compassion. Ambition can be keeping the door open behind you, fighting for other people.”

“I think it’s great to be proud and want credit,” she continues. “Too many times, people are self-effacing. It’s important to have a balance.”

Despite its critical acclaim, Portlandia has weathered its share of criticism, too: in poking fun at the city’s techno-beatnik atmosphere, Brownstein and Armisen have been accused of ushering in the very cultural and ethnic transformation that the show itself ridicules. In Other Words, the feminist bookstore on which Women & Women First is based, wrote a blogpost in late 2016 titled “Fuck Portlandia”, claiming the show’s had a “net negative effect on our neighborhood and the city of Portland as a whole” and that it was “fueling mass displacement”. The store also called out Armisen for dressing in drag to play Candace, which it called “trans-antagonistic and trans-misogynist”.

Brownstein, who often refers to the show as a love letter to the city, is mindful of the censure and hopes, at the very least, that it leads to dialogue. “In Other Words isn’t representative of the entire city, so it doesn’t affect my affection for In Other Words and for Portland at all,” she says. “I’m not interested in putting work out into the world that’s bland, so to me it’s perfectly acceptable, and I actually relish the opportunity to engage in conversation with people.”

The pushback against Portlandia, though, seems emblematic of a certain overly dogmatic quality to cultural criticism these days. As we’ve turned to television, film and music as agents of resistance, Brownstein suggests, the art itself risks becoming homogeneous in both form and content.

“I think it’s OK to make art for the sake of making people laugh,” Brownstein says. “It becomes too prescriptive to say, well, ‘Everything has to have this kind of message,’ because people experience the world in different ways and at different times. If our aim is mediocrity then we can continue down that path, but you have to have a spectrum. If everyone is aiming for the same bullseye, and someone is prescribing a right or wrong way in terms of methodology, we will end up with a lot of replications.

“I really admire work that can address modern-day woes,” she adds. “But I don’t need that to be the only voice in the room.”

• The final season of Portlandia begins on IFC on 18 January with a UK date to be confirmed