that entire service you used that password to login to is compromised
If the password is compromised, it means the service is compromised and the password isn't really protecting anything anymore. So to me, there's no functional difference between passwords and passkeys once a service is compromised, the data is already leaked. If I'm using proper MFA, there's no rush to reset my PW unless the service has a stupid "backdoor" that can just bypass MFA entirely, in which case passkeys wouldn't help either (attackers would just use the backdoor).
The main value of passkeys, AFAICT, is that they're immune to phishing attacks. Other than that, they're equivalent to TOTP + random password, so a password manager that supports both provides nearly equivalent security to a passkey (assuming the service follows standards like storing salted hashes). And honestly, if you use a solid form of TOTP (i.e. an app, not text or email), password security isn't nearly as critical since you can make up for it by improving the TOTP vault security.
I honestly haven't bothered setting up passkeys anywhere, because I don't see any real security benefit. If a service provides passkeys, it probably already supported decent MFA and random passwords. The services that should upgrade won't, because they've already shown they don't care about security by not providing decent MFA options.
In short:
- passkeys > passwords
- passkeys == random passwords + TOTP
The venn diagram of companies that support passkeys and companies that supported/support random passwords + TOTP is essentially a circle, with the former enclosed in the latter. So I don't really see any rush to "upgrade."