[FairlyInvolved]

I really don't see how the current hashrate is required to prevent a 51% attack, that seems way beyond what is necessary.

These Proof of Waste systems aren't really a negative feedback loop, ultimately asset prices determine mining yield. Capacity will keep being added to the network until the difficulty rises such that you are required to destroy $99.99 of resources for $100 of crypto. Until that point it's worth buying more hardware and energy as you get a positive expected return.