You'll almost certainly never get rid of a long tail of compromises in this area, and some tricky parts will be left up to the service provider to get right (there's nothing stopping someone from bungling the password reset feature, for instance.) But at the end of it all, WebAuthn is here today, it axes multiple major vulnerability classes that are used to compromise accounts globally every day, and any future improvements are going to start from that point.
To be honest, at this point the only people I see hanging onto passwords in 2021 desperately are nothing but computer people like us who have been doing it this way for 20+ years and don't want to change out of stubbornness rather than any kind of actual analysis (this exact dynamic explains a lot of things, actually.) Most normal people already use e.g. federated login mechanisms like FB Login or password managers and don't care if the underlying auth mechanism changes this way.
and to be honest, i'm glad to see it! it's huge!
i just push back because history tells us that leaving something that big as an exercise to the reader means that it will be gotten wrong and, well, i'm not sure if you really get too many shots at getting the whole web to upgrade authentication methods.
there's been some interesting articles in vice magazine recently where they talk about the expense of mitm'ing someone's text messages only costing about $5. i'm sure as soon as phishing goes away, as a result of something like this, all the fraud will shift to the next easiest weakness, which seems like it would be underspecified standards for resetting one's public keys/credentials/etc.
fixing phishing is a nice big start, but i keep hearing about all these sms redirect attacks and other attacks on password reset functions. leaving that as an exercise to the reader doesn't really seem to solve the problem. (especially in events where all keys must be rotated due to lost/stolen/compromised device)