If old men want to sit around and complain about how the world has gone to hell with the current generation by only choosing the narratives that illustrate their points, then why cannot scientists and nature people want to hold on to the ocean as it is today? Neither are all that reasonable as the only constant is change. The more reasonable approach is that old men get dumber when gathered into groups, deniers are still ignorant since they never seek any opinions other than their own and that new reefs will form/migrate into cooler waters probably like they have for millenia, but we just did not know then (there was a coral reef covering most of Utah at one point). However, it is still OK to listen to old men since they might have something useful to say every once in a while, and also listed to scientists for the same reason... seeking out a different opinion is part of enlightenment.
I do not know that slight temp shifts don't affect corals. I know the opposite. Turn your tank up to 83-84 and let it sit there for a year or two. A few few swings up that high during the summer might not hurt much, but constant high temps will ruin your reef. Do it and see.
