This blog by Vermaden is probably one of the most cited in the FreeBSD community when someone in a forum/subreddit asks why FreeBSD. I think it does a good job encapsulating the reasons one would choose FreeBSD over Linux or other OS’s.
I’ve become more partial to the *BSD’s in the past couple of years and respect what each one brings. I do daily drive Debian tho ;)
it actually doesn’t take too long. OpenBSD’s install process is actually quick and really straightforward. Here are two resources that helped me:
https://www.c0ffee.net/blog/openbsd-on-a-laptop/
https://sohcahtoa.org.uk/openbsd.html
Also, OpenBSD’s man pages are updated with each new release, and the FAQ is a good thing to check out:
https://www.openbsd.org/faq/index.html