I haven’t looked through the entire thread but the challenge of recovering from a PoW 51% attack is that the attacker still holds ASIC mining power and can re-attack each new fork. The same is not true in PoS where the attacker’s funds can be targeted and effectively depleted in a fork, leaving it prohibitively expensive for the attacker to continually attack each new fork.
See the “spawn camping” description and defence in my prior link.
See the “spawn camping” description and defence in my prior link.