If you talk in the time scales of millions of years, yes. Otherwise it is not true. Global warming has the potential to eradicate most marine life as we know it

If you talk in the time scales of millions of years, yes. Otherwise it is not true. Global warming has the potential to eradicate most marine life as we know it. And once it is gone, it is gone for all the time scales relevant for humanity. And we do not know how far the ecological impact would be. Just killing the coral reefs would be a tragedy, but if we are unlucky, this triggers enough eco systems to collapse that also our direct survival is endangered.