I feel sorry for your situation. But at least in lemmy the dev are willing to try to resolve this problem. Low chance is still better than zero chance.

Here is an wild idea. Since a few communities are so divided and clearly they only have a good time when they talk to ppl exactly like them. Flame war happens when two groups of hardcore opposed users argue. Since normal users won't have all days to argue with either side, if one side leaves, the wars is ended.

So instead of banning users by admin or blocking one users each time by users. Can we have allow users to create their own public group (or a gang)? Users can join any groups. Instead of blocking one user, users can simply block the whole group. Posts and comments will be hided if blocking.

Advantages:

1. No banning is needed means admin's time and gang members' time can be saved.
2. finally no one disagree with those gangs members anymore, so I guess they're happy
3. instead of using time from admin and uninvolved users, users who frequently involved controversial topics everywhere should spend their own time to create a group for staying in their comfort zone.
4. uninvolved users don't have to read all those flame war

Disadvantages:

1. those gangs become more extreme cuz they miss the opportunity to understand each other
2. dev have to do more work
3. server may have more load
4. some users might say those gangs should host their own instances

Ps: I don't use the term community because our board is also called community. I don't want to mix them up. May be i should call it users group, but I am too lazy. I do agree better word should be used.