I think it is a good idea. We pretty much did just that when consolidating c/SpaceX from !SpaceX and !SpaceX to !SpaceX. I just now noticed the dormant !SpaceX. Should that be consolidated as well?
Another candidate for consolidation? A bit of a tricky case, as the current largest community is not on the most politically centrist/neutral instance, and lemmy.dbzer0 which (in my opinion) would be a more closely aligned instance doesn't have a data hoarders community.
Is it a good idea to post to abandoned communities about their active counterparts?
I'm mostly thinking about LW communities where nobody posts but which have active counterparts on other instances