We must limit the problem, then adapt and mitigate. Some damage is irreversible, it does not mean that it’s a good idea to stop trying to understand what will happen. You don’t stop weather forecasts when a hurricane touches land just because it’s going to happen anyway.
Reality is not binary. There’s a whole spectrum of situations between "everything gets back to normal and all is well" (which was never on the cards after the 1980s) and "all humans die within a century". And the nuances in between still affect billions of people.
From what I understood we are closer to the “all humans will die within a century” and if this is the case then what’s the point of doing anything? Does it matter if our effort just delays the “all humans will die” by let say 50 years? Radical change we need to do if we are serious is going back to caves. 0 consumption. I highly doubt anyone will do that.