Why is this womans board so popular right now?

She's a special person who got famous for getting angry

This board is on fire right now.

She's basically telling everyone that they're doomed and that the world is coming to an end. And that's what people, especially religious people, love.

Some people have weird fetishes, that's all.

Now seriously, she's just a religious figure. She's a modern replacement for the traditional 'saints'. Judeo-Christian religions (and the Modern Left is just another one) have some kind of soft spot for child saints:

https://en.wikipedia.org/wiki/List_of_child_saints

She's the Mascot for Leftist Agenda.

She is a young activist who sailed across the Atlantic ocean alone to raise awareness about climate change. She gave a speech at the UN, and has been invited to speak at other venues across the country. She also has Aspergers and overcame many symptoms to become a confident public speaker on an issue she cares deeply about.

Couch potatoes are jealous of her because she is only 16 and has accomplished more than any of them could do in six lifetimes.

That's not a woman. It's a 16-year-old potato with a Dorothy wig slapped on that two greedy, selfish Swedes brought with them to the UN.