> BIG citation needed.
While it may be debatable how much of an effect the OpenBSD security culture has on real world security outcomes, it is pretty obvious to most people I think that OpenBSD has a culture of security (or a focus on it) that Linux simply does not have. Security is practically the entire branding of the project. Just go to its home page, literally the first sentence is an advertisement for its security record. The culture is very much there, regardless of results.
Now, if you did want to argue that the security culture does not necessarily result in better outcomes, 1) that intention should probably be made more clear, and 2) why not at least provide an argument or some amount of evidence for it?