Also PieFed allows blocking all users across an entire instance, whereas Lemmy does not (I know that you know that, but in case it helps anyone else reading:-P).
Addendum: Yes we know that you think ml/hexbear/grad are tankies and or .world are a bunch of liberals but it gets old quickly. Try and come up with new material.
Piefed has keyword filters, that can already help a lot with filtering
Also PieFed allows blocking all users across an entire instance, whereas Lemmy does not (I know that you know that, but in case it helps anyone else reading:-P).