The globe is currently in its warming phase, and just like when it is in a cooling phase, will be undeniably bad for some, and undeniably good for others. Sea turtles? Gonna be real bad for em, and any other aquatic animal that lays eggs in sand in order to control sex percentages in their population. They live a long time, but by the time Gen Alpha is old, baby sea turtles will be impossible to find.

Deep sea creatures? Gonna be doing just fine - the ones who chill by volcanic vents will literally never notice a difference. Most bird species will continue to do well, even penguins will probably be able to create a niche in warmer waters - they already enjoy spending time in South America, and they are excellent aquatic hunters. Hundreds of fish species will perish as the oceans continue to heat, while hundreds more will see the greatest population booms in the history of their species.

Plants will naturally grow ever larger and lusher as the amount of CO2 in the atmosphere cyclically compounds upon itself (even if every car and cow disappeared tomorrow, the amount trapped under the rapidly melting ice guarantees a CO2 feedback loop that will massively stimulate plant growth), which should help balance out the reduction and even loss of certain key pollinators. Besides, pollination is one of the oldest niches and insects have such short iteration cycles, something will fill in.

Larger mammals, especially those at the poles or who need a lot of water in and around them will do badly, while the smaller scavengers will do very very well for themselves.

Humans as a species will continue to exist just fine, especially as long as we have access to cooling technology, though certain population centers will become uninhabitable. The real issue, the real “crisis” that COULD happen due to the globe doing it’s thing and warming like it does from time to time, is not the raw specifics of creatures dying. That happens all the time. It’s our economics being made fragile during the window where specific species die out and new ones haven’t yet filled the niche.

The niche will be filled, but on the timeline of the planet, not the quarterly expense report. And of course, there’s the potential danger of chaos caused whenever there’s a large exodus of humans from one place to another place where humans already are.