One part of the thing is that oil interests are far too powerful and people are far too complacent. We "could" do something but there is far more short-term economic incentive to not. We could all stop 80% of our polluting tomorrow. It would be super uncomfortable and probably boring, but we have done worldwide action in some form, as we saw in the COVID pandemic. But it's too convenient to just keep doing what we're doing.
The other part that I don't really see this author mentioning is feedback loops. When warming gets to a certain level, it can beget more warming. Icesheets that reflected solar energy back to space is now being absorbed by the oceans. Permafrost melts releasing trapped gasses. The ocean heat currents are weakening.
Now I enjoy optimistic takes. I do think it is possible to turn things around as a planet. But there is an overpowering collection of voices saying "I don't wanna" that need to be overcome. The natural disasters are still going to have to get worse before people want to do something about it. And I haven't even talked about human conflicts causing needless suffering.