Info pages
When well conceived
they are structured and you can navigate with links.
Linux "users", better say Firefox users or OpenOffice users are just able to click links in their browser. Hence many basic information comes in html "user guide" form.
Projects as
http://tldp.org and
http://manpages.courier-mta.org try to put a collection of man pages together.
But, mission impossible, this will neber include variants that coders at some distros consider as "improvements".
To mention: FreeBSD on-line man pages with a collection from many OSes.
Difference of culture:
Linux coders are happy if their GPL'ed applications do not break too often. Usual answer to a PR is the Microsoft styled "get the latest version". Man pages? Must get the code working first.
On OpenBSD, an application will not make it to the ports tree unless the man page is comprehensive. The team will first read the man page, then, eventually, have a look at the code.