Greta Thunberg(tm) is a politico-business franchise. She is a sock puppet of the loony left.
It's giving her rock star status and validation. I pity her when she is old hat and not trendy any more.
As for the kids that supposedly support her; most of them are probably just using it to bunk off school.
When the Thunberg(tm) franchise goes to preach in China and India (on a yacht ), I'll be impressed.
Climate is another issue, of course. The loony left are using it to promote their neo-Marxist fascistic control.
Swathes of blue haired feminazis and cowardly SJW antifa thugs line the streets (if they can be bothered or have the energy to get of their sweat sodden couches as they whinge on Twitter), to shut down opinions that hurt their feelings on the matter.
Bottom line, I think most of this is just a trend for attention seeking trendies and sad losers.
I'd like to be proved wrong......but I doubt it.