And it's not like shutting worlds down is something that will happen long term to 1/2 of the existing worlds. Shutting down 3 worlds is 96 slots.
Take, for instance, MHLB. They have 21 openings, thus 11 filled teams. Let's say 9 of those owners pick up another team, and 2 get ****** and leave. That's 21 + 9 (which equals 30) fewer openings. Do this a few more times and things all of a sudden look pretty reasonable.
And if nothing else, this over-supply of HBD teams has at least been useful for some interesting discussion. :)