OpenBSD pioneers a lot of security research and best practices but I think many people get misled by all the hand waving and subsequently have more faith in certain features and less knowledge. I'm a victim myself.
As an example, I recently brought up W^X and wanted to know what the status / stance was and was met with a healthy dose of skepticism. As I was told, "W^X is very useful for debugging but not for security as the kernel has a read-write 1:1 map of all physical memory... you can still write to memory that will later be executed, you just have to use a different address" (not a direct quote) This was completely new information to me that nobody seems to talk about.
Likewise when I asked about securelevel=1 -- I was met with "securelevel is more likely to be removed entirely than enabled by default ... not convincing because there's no coherent model ... easy to work around as an attacker unless the system is very, very carefully configured, which means it's locked down beyond usability for most configurations ... though it's useful for jails since you can still do maintenance from the jailhost"
tl;dr I think the FreeBSD devs who can call the shots are more interested in ASLR and pushing Capsicum hard.