At one point, SELinux being on by default made one of the Red Hat distros a pain. This high-friction first impression cost them some adoptions, when an IT manager did a test install. A "softening guide" might've helped.
IIRC, managers were qualified sales leads who were actively looking to move to a supported Linux platform, but got turned off by the installer&docs out-of-box experience that seemed like it was going to make a lot of extra work for them.
I just meant the "softening guide" might've helped from the perspective of the company who'd like to land those customers. I don't think it's the best way, but at the right moment it might've salvaged some sales.
You may be describing OpenBSD ("secure by default") and its FAQ (how to do what you want with it). The OP's hardening guide might be largely seen as going to greater lengths than most people need. (I use its advice about umask, though.)