I reckon this Greta Thunberg will be an interesting one to watch. She was all high and mighty as an obnoxious child back in 2019, but watching recent interviews as she's got older (and hopefully wiser), her message is slowing changing to be not quite so black-and-white... Funny that.
I suggest you actually look up whats she's done since 2019, including the "Blah, Blah" speech in 2021 and as recently as 7 days ago rubbishing the COP27 as "greenwashing, attention seeking leaders". Still some very black and white comments about achieving fast actual change rather than slowly through the normal political process.