You seem to be coming from a place of knowing about comicsgate and have particular cares about it. Handman clearly doesn’t even know what it’s about so it’s not fair to say he is expressing callousness to you particular concerns. You could say, hey the name sounds dopey but it’s actually something important because X reasons. Maybe he’ll agree with you or maybe he’ll have more contrarian views about it. You seem to be way overreading Handman’s post.
In that case, is it not callous for someone (with no knowledge of, let’s say, the Holocaust) to say “I hate all this bitching about the Holocaust which is of no consequence to me.”