Earlier quoted context omitted.
Road warriors with Thunderbird may need SMTP authentication, but most people do relaying with just IP authentication just fine.
Aside of the fact that I doubt your "most people" assertion here, it's beside the point that I was trying to make which is that a CVE affecting a feature of Postfix that qmail doesn't have to begin with is not a fair mark against postfix. Because if you disable a feature you don't use, you won't be affected by the vulnerability. If you use smtp authentication, you're not running djb's code and all advantages of djb's…
I disagree. It is a fair mark against postfix if (as I claim) most users really don't need it.
Here's my reasoning to that point:
I think most email end-users either use their ISPs mail settings (who know who they are and don't need authentication), or webmail (which doesn't use SMTP for relaying anyway), or outlook (which doesn't need SMTP at all). Fastmail is becoming more popular and it doesn't need SMTP either. The end-users who remain are either business users (who could use a VPN which is better than SMTP AUTH in every way), and nutters with vanity domains.
If that's contended, and note I do believe there are probably end users who are actually still manually entering SMTP AUTH settings into email clients, but I would struggle to believe they're the majority and would need evidence.
Meanwhile on the enterprise, pretty much every machine in every enterprise environment I've ever worked in has been set up for local relay. Again, if you think they're all using SMTP AUTH I'd need to see evidence.
> If you use smtp authentication, you're not running djb's code and all advantages of djb's code are moot
Do you actually believe that if you apt-get install postfix that you don't have any of the advantages of postfix's development processes?
I'm not sure I can engage with that. It's like saying running linux invalidates "all advantages of djb's code" simply because you're (sometimes) not running his code (e.g. when you're in a syscall). Madness runs down that way.
For what it's worth, most of the qmail smtpd patches I've seen to add SMTP AUTH (including the one I wrote nearly twenty years ago) are sensible, integrate well with the rest of qmail. You might not get djb's warrantee, but I can't believe you gain nothing by starting from a solid foundation.