Agreed, the reason I chose beehaw, among other things, was that the focus of other instances was growth for growth's sake, while beehaw seemed to be looking to cultivate a more thoughtful, moderate growth, avoiding lowest common denominator problems that Reddit was plagued by by 2014.
So my rule of thumb would be more to ask "do I personally want to talk about this" than "is this popular and getting engagement" before thinking about posting something.
That's interesting that lemmy doesn't generate canonicals. I would have thought that the original instance something is posted on would set the canonical, and other instances can point back to that - it really seems like this sort of problem is exactly what canonicals are made for. Does anyone know if there's a reason for not using them (other than dev time, which is 100% a good reason)?