Given that LW is “too big” and can be a bit buggy at times, and ML is a general-purpose instance with an unmodded community, I’d argue that consolidation should be from LW and ML and towards programming.dev if anything. It’s the right size, and it matches thematically. Usually, when people are proposing consolidation, it’s away from LW, not towards it.

I’ve no strong opinion on the pros and cons of shutting down ‘other communities’ - I just collect similar communities in a Feed, and see all the posts that way: e.g. https://preferred.social/f/hardware - it’s maybe better to wait until Lemmy implements a similar feature, to avoid the inevitable arguments.