A clear-cut and uncontroversial rule that will see little to no opposition, yes.

And in many cases it's also clear-cut and uncontroversial whether someone is a fascist or a bigot.

But in other cases, you're going to run into trouble. A particular case in point; I don't like the Disney Star Wars sequel trilogy. I have, in the past, been immediately called a sexist when I've mentioned that fact. But I personally don't care one whit about the gender of the trilogy's protagonist, I just think they're bad movies. Maybe there are other people who actually do care and that's the reason they don't like those movies. Maybe there are people who don't believe me when I say I personally don't care about the gender of the trilogy's protagonist. So, is https://reddit.com/r/saltierthancrait/ a bigoted community? If there was a Fediverse equivalent, should it be blocked? Different people will argue different ways.

I can think of lots of other scenarios, I won't make a big rambling list because I'm sure I'll step on a landmine eventually. I'm just arguing that seemingly simple straightforward "rules" that are easy to agree with can still end up mired in complexity when people try to implement them in the real world.