It's 2021, and that means Greta Thunberg can lawfully grab a beer in her hometown pub. Of course, to someone who's started a global movement, dressed down heads of state and fronted Time Magazine as Person of the Year, obtaining Swedish drinking rights may not seem like a big deal.

And yet in her unlikely rise from 15-year-old school protester to global icon, Greta's reaching official adulthood is noteworthy. She made global headlines on her 18th birthday back in January, taking the opportunity to troll her critics: "Tonight you will find me down at the local pub exposing all the dark secrets behind the climate- and school strike conspiracy," Greta tweeted.

In Sweden, right-wing media was quick to fire back, with social media posts and publications pointing out that Greta could from now on be safely criticized, without anyone being accused of attacking a "child."

Is it a good thing if her pessimistic brand of activism has run its course?

Of course, pre-adult Greta wasn't exactly exempt from bashing, having been called everything from ignorant to naive to mentally ill over the last three years. But the question now is what growing up means to someone whose youth was her superpower with a message that began and ended with: "We children ..." The pigtailed, stern-faced kid who skipped school to tell adults they've stolen her childhood and are ruining her future is now one of us.

Greta herself, we know by now, would say "it doesn't matter," if her time representing the voices of the young has run out — it's not about her. And yet there she is, slapping ministers around and half-or-not smiling in photos and being an overall total pain in the collective rear of the Davos establishment. A week ago, following a digital climate meeting with Swedish Prime Minister Stefan Lofven, Greta dismissed him as yet another politician in denial about the true urgency of the climate crisis. And what did he expect? Lofven might be an outspoken supporter of Greta and leader of one of Europe's top-ranked countries for climate action, but Greta is Greta, and that doesn't include supporting this or that — politicians are hypocrites and international climate summits are empty words and greenwashing.

Indeed, by now it strains you to imagine the type of climate action Greta would endorse, and it begs the question: Is it a good thing if her pessimistic brand of activism has run its course?

A Greta Thunberg mural in Dublin, Ireland — Photo: Artur Widak/NurPhoto/ZUMA

Last December, back in Sweden after a long period abroad, I was curious to hear the thoughts of mine and Greta's compatriots. Zigzagging through a rainy Stockholm, what did my taxi driver think of our country's most recognizable face?

- "I guess she means well…."

- "But?"

- "That's all." Then, after a few pulls and drags: "Well, her ideas seem a bit unrealistic. She's very young, after all."

What Greta calls denial is in fact a wager to keep the economy going.

This turned out to be a general opinion. Throughout my month-long stay, most people answered that Greta was necessary but impossible. Last year, after she scolded the EU Commission for setting mid-century objectives rather than taking immediate action, Vice-President of the European Commission Frans Timmermans made the same point, acknowledging Greta as a force driving the proposal forward, but added that "we're more optimistic than she is about new technologies that can help us accelerate the process."

So what Greta calls denial is in fact a wager to keep the economy going. World leaders are of course aware of current carbon reduction being insufficient to limit the warming of the planet, but are betting on reaching a tipping point where clean-energy technologies become scalable enough to change the equation. From that standpoint, Greta's brand of activism, which she has acknowledged to be driven by "moral superiority" and "shaming," is counterproductive.

From where I stand, somewhere between Greta and Timmermans, I still remember my own teens of bulletproof convictions and misguided indignation. But I also remember, before the self-generated fog of adult rationalization took over, those moments of real clarity where my future appeared as it was, not what someone promised me it would be.

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