Ignoring the consistency arguments, limiting quote reuse raises quite a lot the complexity. This is because when parsing the expression part now the parser needs to be aware that is parsing an expression inside an f-string with a given quite, and that becomes even more tricky when f-strings are nested with different quotes.
This doesn’t mean that this invalidates the “code smell” argument by any means: I just want to give some context on the maintenance point. I totally understand why you voted “no” (and that’s why I really want feedback from everyone).
I think this is an important point that I guess is not going to have an easy answer. But I promise that we will do our best to reflect all of these considerations in the PEP when a decision is taken and to take all of these into account for our final proposal.