Would the Ethereum of today [proof of stake, i.e. lightly inflationary but mostly rebasing, with inflation rewards going to holders, with most payment activity happening using fiat-backed stablecoins] have been adopted in a parallel universe where Bitcoin [a 'hard' money system where tokens only are created only through demonstrably large amounts of work via trapdoor functions, and that intentionally only serves as a payment network on its own currency] had not been created?

To what extent did we need to see how Bitcoin solved for decentralization and censorship-resistance, as well as the quirks and extreme costs, in order for the Ethereum construction to feel familiar but better?