If the system does not depend on a central authority
In your example of coalescing on a single community, the mods of that community are the central authority.
it’s easy to coordinate a move away.
It's not even easy to coordinate everyone moving to a single community. This issue has been discussed in various forms for more than 3 years and we haven't seen this supposed consolidation of communities. Coordinating anything in a decentralized way is never easy.
That doesn’t bother me, and I truly don’t understand why it should bother others. I am not going to write only if I am optimizing reach or I know a priori if the people are going to approve.
Cool. It doesn't bother you. Then just keep doing what you're doing. If we ever get a solution to it implemented, you won't care but the rest of us will be happy for it. If you don't care, why are you all over this thread arguing about this?
This isn't about maximizing reach of our posts. It's about consolidating discussion so that communities (especially those with more niche appeal) can have a sustainable userbase and not die out from lack of activity.
That's not applicable. Sublinks is using the same standard as Lemmy/kbin/mbin, i.e. ActivityPub. In a decentralized system based on an open standard, plurality of implementations is a good thing. We shouldn't want lemmy to be the only one.