I've heard a number of conflicting arguments about the reliability of Ethereum switching to proof of stake... From "they will" to "this is difficult, why bother". There's also the other side of the equation - what's the value-add, and is it justified by the consumption? (e.g. the banks, trucks, etc. do something for the financial system, which has value. Is value / cost higher for BTC or lower?)

I do not know.