Considering that it's going to be really hard to enforce any other filter in thousands of clients, separate accounts can solve it without any need to support it. It's more work, but it's also better for your audience.
We are working on NIP32 labels and communities as subtopics per account, in such a way that you can follow or hide just a subtopic from a user. That will make it better but almost no client will support it out of the gate... It will take a LONG time.