The network does. Difficulty goes up. Security goes up.
Security goes down! These nodes are all serving the designated pool.
Profitability goes down. Big farms fade away. Maybe. Who gets those Bitcoins does't even matter much. Burn them for all I care.
Myopic. Big farms are just usury. This is same usury that is backing utilities. The real profit comes from a monopoly on money, what we were fighting by supporting crypto.
Of course 21's chips will probably just mine on a pool, which might make things worse than ever. I don't claim this is some kind of cryptonirvana. My comments were focused on the question of efficiency.
How can we have a meaningful discussion if you pigeonhole to the irrelevant factors only.
This is not about energy efficiency. You argued very hard that is it about efficiency (energy or otherwise).