OpenBSD only has a small number of precompiled packages, and usually extremely outdated. If you want to get
anything useful you have to compile ports. As for the question of whether Linux being widespread is due to marketing or quality: that is completely irrelevant. The fact that Linux
is more widespread is all that matters. We don't live in a theoretical world where only theoretical technical superiority is the only thing that matters.
You are right, no management and administration tool is more superior than the Unix command line. The thing is, Puma's Unix command line tooling is almost nonexistant. All of Passenger's management and administration tools are command line tools.
You are also correct in that you don't need fancy software to do things for you when you can do all that stuff yourself. It's a bit like saying that Docker has no added value because you can setup LXC yourself. But it's not hard to imagine why so many people do find value in Docker.
As for spam: yes you are right, there have been times in the past when we were overly eager with promotion. I apologize for that, and we've since adjusted our strategy.
Having said that, our claims have always only been based on facts. For example: how do I find out what requests my Puma processes are currently handling, and how long they've been active? Where are the tools to query that information?