It wasn't that surprising that a large amount of them moved on. A family member is police officer and he said after a while you notice that, no matter what the cause is, the same people turn up at protests.

This essay highlights the issue pretty well. Regardless of what the thinking is or intentions, it is the view from the outside that matters. When the face of XR Greta Thunberg started turning up at Pro-Palestine events and trying to drop goods off directly to Palestinians, she can be totally since and well meaning but the message gets muddled.

To bring this into the technology space, this is something I actually really admire about Richard Stallmans work with the Free Software Foundation. I have repeatedly seen people just to attach their cause to the movement but RMS has consistently refused as he doesn't want the cause to be diluted. Yes, Stallman personally has a lot of political views and makes them very aware on his website, but he tends to compartmentalize them from free software outside of the occasional joke.

There are still many that are involved in Climate change awareness but their numbers are much smaller than the last swell that came along a few years back. It can be demoralizing seeing your movement just be a flavor of the month rather than a longer term goal. This is why places like 'The Dark Mountain Project' formed, it is made out of disenfranchised ex-environmentalists. They still believe in the cause but have no faith that others will come along with them.

A part of it is also probably due to the perceived higher velocity of news and events thanks to the internet means that it can become difficult to keep people interesting in somethings long term. This is partially why XR did their publicity stunts, it was a way to cut through the noise. But, as someone I knew who used to chain themselves to trees once said to me "Eventually the public builds up anti bodies against extreme political acts.".