This list should clarify things a bit.
While OpenBSD had ASLR it is lacking in many other ways.
That is the thing with security, it isn't the doors you locked that matters, it's that single one you didn't lock that is the problem.
Hmmm... While I agree with you on the general principle, here are a couple of things, off the top of my head:
1. False positives ("Vulnerable" tests in your example) do exist, you know. How are you sure that OpenBSD (or FreeBSD) is vulnerable in such and such case? Have you created an exploit specifically for the things being tested by paxtest? Maybe OpenBSD has other capabilities
2. False negatives are also a thing. Even if paxtest says: "such-and-such is OK", how do you know if a clever hacker won't be able to find a way around the ASLR protection?
Also important: paxtest dates back to 2004, and, as far as I know, has never been updated since (web site here). Not that this is a bad thing, but ASLR, and security, has changed a lot since then...