Not sure about ethics, but if the argument of "excessive moderation overhead" still holds true for staying defederated from Lemmy.world, the same should apply a thousandfold for Threads.
yeah i mean this is the veto even if we wanted to do this (which we don't) and even if the community wanted it (which they clearly don't seem to--nobody's clamored for us to federate with Threads). even a tiny fraction of a fraction of threads being involved with our site would probably top the peak of workload we had when Lemmy took off. there is no current realistic circumstance in which we'd ever choose to or be able to federate with them.