But the [5 reasons] aren't a problem?

In my experience, the Hexbears are often weird and annoying and wrong, but not in a way that's illegal or that I think warrants deplatforming. So ideally, in situations like these, the solution would be for individual users to be able to block entire instances and share block-lists with each other. I've heard that this is possible with uBlock Origin and sort of possible with one of the mobile clients, but it really should be a known and user-friendly feature of Lemmy itself.

As long as this isn't a feature, though, then obviously Hexbear should be defederated if that is the will of the majority of Blåhaj Lemmy users. I'm just speaking for my own experience, having not really experienced any of those things you've described. Ten people, ten colors.