There won’t be any legal fees since the communities being talked about are allowed in the EU. Other people have made the same point already, but if you are scared of litigation, then you can’t host a forum at all. There is always a place where your forum breaks rules. I.e. no disparaging Putin in Russia. Making fun of the twitter CEO is more likely to get you a lawsuit than any of the communities mentioned, yet it is allowed. Also, it never is a straight up instantenous lawsuit. It always starts with communication saying “don’t do that anymore please”. Once you reject, then a lawsuit is viable and not frivolous. So you can wait till that happens and then block those communities, once a company actually complains. Not when you think that maybe somewhere in the future something might happen or maybe not.
Truth is, lemmy is small fries. It will be that for a long time with the issues it has. Nobody cares about a tiny community hidden way deep inside.