I assume once the bubble bursts they'll be turned into power supplies for bitcoin miners
Hopefully not, but they expect that scenario. For those as ignorant as me, I started reading this https://cointelegraph.com/features/the-last-bitcoin-btc-mine
They expect transaction fees will overtake minting earnings.
I saw more than one video about datacenter noise that were clearly crypto mining. There are some questionable designs leveraging shipping containers and what sound like a lot of 120mm fans.