So ... any constructive suggestions, then?
One comment on here seems to sum up the attitudes of most contributors:
"If these are the people trying to save the planet I'm afraid it's doomed."
While I agree that this is an own goal for the people concerned, I can't help but think forward a few years to those of current adult generations ('us') being asked: "What did you do in the great struggle to reverse climate heating, (Great-)Grandad/Grandma?" I can't see anyone here coming up with suggestions.
The author of this piece, Kieren McCarthy, understandably slags off the protestors, but at least says:
"Of course, climate change ... is a serious issue; one that can and should be tackled in a multitude of different ways". He doesn't name any, however.
My spouse and I are currently conducting a review of what we can do ... thinking that it's all very well signing up for a 'green' electricity tariff, but that was 10 years ago and I'm still commuting in an ICE car! We'll probably buy a BEV in 2020 to replace it, but what can we do to help put pressure on the big energy companies, to make them stop their egregious campaigns of misinformation and just 'leave it in the ground'? Is it worth getting out at weekends to plant trees? What can we say to friends and family that would help? What political campaigns are constructive and might be effective?
So then, I shan't be on the streets or trespassing anywhere on September 20th, but I am taking the day off to review what we know and decide on some next steps. If you understand my motivation, then wish me luck. If you don't, have another look at the evidence and use your imagination. Then think again.