It would be a lot more manageable than some centralized list that tries to capture every user controllable content domain on the internet.
- OCSP if not stapled.
- IPv4/IPv6 racing/Happy Eyeballs.
- Encrypted SNI (DNS lookup).
- Certificate Transparency: some Chrome builds are now querying logs to confirm embedded SCTs (if I understood correctly).
and now:
- Related Domains by DNS (draft-brotman-rdbd-02), or whatever replaces the PSL.
RDBD would have to be in the critical path (in order to understand the cookie scope), it's just going to make things slow and complex.
Are we also gonna give the same treatment to the HSTS preload list?
Not sure why you feel there is arbitrarily "too many", do you have a concrete objection?
I'm not so fussed about extra queries when they do not delay the user. But if we send out a RDBD query that a resolver doesn't respond to in a speedy manner, what does the user-agent do if it needs to decide how to scope a cookie? You can't exactly soft-fail something like that ...
Like most things, on first glance, it seems like it does make sense. Except it has a lot of issues, which you can see have been discussed for 15 years without resolution, even though yes, it would scale better.