Earlier quoted context omitted.
PoS opens up new threat models concerning the tyranny of the majority. PoW utilizes the honest indicator of un-forgeable expense to mitigate this class of risks.
A class of risks that the normal financial system doesn’t have. My bank doesn’t expose me to “double spend” attacks.
There was some error with the debit card system where it wouldn't accept my card, then when the cashier rebooted the device, it informed me that my account balance was insufficient. Sure enough, checking my balance I see that somehow the first try "stuck" into the system as a 'pre-authorization' -- inexplicably unusable money. The bank just shrugged, it would fix itself in two weeks.
I stopped paying with plastic. Fear the day the ATM fails to produce the bills yet drains my account.