I don't know what "world+dog" refers to. I think it's actually fairly likely that they will successfully transfer to PoS fairly soon (like, maybe by the end of this year, or end of next year), but until they do, any concerns about "participating in the network can increase the amount of electricity that miners are incentivized to use, and I don't like that" are still valid, and it doesn't make sense to dismiss them on the basis of "they will switch to PoS soon." .
(Perhaps if part of one's concern was that using it would contribute to how much the network will be used in the long-term future, them attempting to move to PoS might do a fair bit to alleviate that part of the concern, but I don't think that is much of people's concern about using it, and so this is largely irrelevant.)
Given Bitcoin only contributes on the order of 0.1% of global CO2 output, I think it's mostly the long term concerns, of how much crypto could emit in the future if it became mass-adopted, that are justified, and Ethereum's PoS plan address those.
