In case there's ambiguity here, I think GP means "core to the ideals" of Bitcoin, not the core of its implementation.
GP is correct. The Bitcoin community is fiercely conservative, and a proposal to switch from PoW to PoS would be met with about as much scorn as a proposal to increase the total supply.
Ethereum, on the other hand, has never had any strong attachment to PoW -- quite the opposite, really. Switching to PoS has been a major goal since the early days of the project.
GP is correct. The Bitcoin community is fiercely conservative, and a proposal to switch from PoW to PoS would be met with about as much scorn as a proposal to increase the total supply.
Ethereum, on the other hand, has never had any strong attachment to PoW -- quite the opposite, really. Switching to PoS has been a major goal since the early days of the project.