I think it’s the opposite. The more doomer we get, the more change is likely to happen.
Climate doomerism is funded by big oil using the same people that did positive smoking PR for tobacco lobbiests. The problem is it makes most people throw up their hands and continue as is because they feel like they can't change anything.
https://www.scientificamerican.com/article/climate-deniers-shift-tactics-to-inactivism/
PBS: https://www.youtube.com/watch?app=desktop&v=AeqAoozVyfQ
I may just be speaking for myself. But as a doomer, it motivates me. It may not for others. Most doomers I talk to have one goal- make fossil fuel companies pay. I find that inspiring. I believe collapse of society is inevitable due to capitalism and climate. More like a crumbling. It’s already started.