I'd agree I'm cynical, but it's just my opinion based on everything I've read and seen over decades, not some attempt to brainwash people into inaction. We should absolutely do anything we can to change our ways both individually and overall now that we know the damage we do, but that doesn't guarantee a fix.
It's very difficult to discuss the state of things today without being accused of being too negative and now even claimed to be "the problem". If you want to continue thinking that we could have had a modern society with high living standards and constant growth, then go ahead. It's simply not realistic to me knowing we have a finite world. The bacteria in the beaker analogy is well known to everyone.
We crossed the line maybe with the industrial revolution, but certainly with learning how to use chemical means to provide far more food than naturally possible (Haber process). I fail to see how we can ever get back to that line now, especially since it and everything else we do is heavily dependent on petroleum that's also finite. Hence my comment on restructuring society - unlimited growth is not sustainable, yet it's a cornerstone for us for centuries.
I did think we could fix things long ago, but after a while you begin to see the pattern of hope and promises and realize we're experts at fooling ourselves.