At the risk of setting up a straw man (but the sentiment of your comment seems negative), but should we slow down improved security for the a bunch of tech people who have hardware keys with a measly 20 or 32 slots?

Sure, authentication could also be done without resident keys, but resident keys simplify the authentication workflow a lot, since the relying party doesn't need some additional credentials to send the correct wrapped key.

(Disclaimer: I have several Yubikeys.)