Ecosystems have evolved to tolerate the historical weather, not the 2C-hotter weather. In particular, many ecosystems have had no selective pressure to be able to tolerate heat extremes considerably above the maximum they've ever experienced.

So, when you have an optimized system, change is bad. Animals and people will die. People will starve.

In some other places, extremes might shrink. But that won't save much of anyone because the ecosystems there were already adapted fairly well to the extremes. You don't get much of a boost from having life be a bit less tough.

Hilariously, it's usually people with a conservative outlook--who naturally should understand the principle quite well of the disruption and problems caused by throwing out a tried-and-true method for a newfangled idea--who tend to reject that global warming is a problem.

It is.

When it comes to ecosystems and the humans that depend on those ecosystems, conservatism is the correct viewpoint.