... and I ought to add, given the inclinations of many of Nostr, that it would also allow right-leaning libertarians to vote for candidates who actually reflect their views, without handing the election to the authoritarian centre-right (Dems).

In either case, STV in local and state elections would diversify representation at those levels of government. Which would likely filter up to Congress and the Presidency, whether STV voting was used at that level or not. Making electoral reform there more likely to happen.