One thing I haven't been able to figure out about proof of stake is this: if one entity somehow manages to control over half to the total ETH tokens, does this enable an attack analogous to bitcoin's 51% problem (which happens when one miner controls over half of the network's raw cpu power)?
A 51% staker who attempted to reverse transactions on ETH2 would be automatically penalized by the destruction of their stake. The network would keep running and the end result would be a large sudden deflation of ETH. On PoW this would be like an attacker's mining rig burning down. A 51% staker who just censored transactions could hold out longer. If the problem were severe, the community would have to decide whethe…
A rig burning down will undermine the network's security (as less electricity/capital is invested in securing it), while a stake burning strengthens it (as deflation increases the value of the remaining stake). There's no real Pow equivalent, eth2 is simply superior.