Since, I don't debate global warming, nor the existence of gravity, or that the earth is round, there will be no meeting of minds which makes this discussion rather pointless.
Unlike you I see both sides of the issue. Most of the coral on earth is deep sea coral which is found at a depth of 200 to 10,000 feet. It is basically a cold water coral which is not likely to be effected by global warming at least not any time soon.
The devastation of shallow water coral, which really is critical to long term viability of marine life has been going on for over a century due to pollution and destruction of the reefs. Global warming is making the problem far worst. We know without a doubt the temperature ranges the various species of coral can tolerate and we know the temperatures of the waters where the coral is dying. It ain't rocket science.