Capitalism and democratic systems don't work without growth. Just look at the consequences of the economy stagnating in western Europe and what that is causing on a societal and political level.
No growth means no jobs for new grads, no growth means workers have no negotiating power with their employers, no growth means young people remain poor and cannot afford families. No growth means young people with bad economic prospects seek political alternatives, and newsflash, they far-right with their magic-grift-politics are far more appealing than the far-left with their estorectic utopian far-fetched plans.
Also no growth means a worsening wealth inequality over time.
Growth über Alles / the race to consume everything we can in our spherical petri dish with the same level of awareness as mindless bacteria, will be the end of human civilisation, regardless of anyone's economic beliefs.
Climate change is simply not an extinction threat. Despite all the fearmongering, the worst case scenarios top out at "WW2" levels of devastation and loss of life.
The only credible extinction threat to humankind so far is an ASI oopise, and that's because it's an intelligent threat.
Assuming positive real return on their investments, a zero growth (or low growth) economy means the rich will own an ever growing proportion of wealth - its simple arithmetic.
