ericbsd
I'm not aware of any links from elsewhere to ghostbsd.org/forums - it's just the URL I habitually type in to my browser, though I'm sure my muscle memory will eventually learn not to!
However, it is the "odd one out" on the site, and it is common for websites to redirect path-based URLs to corresponding subdomain-based URLs, eg yahoo.com/mail or outlook.com/login. Or even redirect to a more complex and less memorable path-based URL, like amazon.com/account, amazon.com/books or x.com/login.
I appreciate that I'm in a tiny minority of people who still tries to type by hand the URL they want to visit, like we basically had to before Google came along! Especially since in most browsers the address bar now doubles as a search bar, I'm sure it's now far more normal to type "ghostbsd forum" then click through to the first search hit! Personally I try to avoid this - unnecessary use of search engines has a depressingly high environmental footprint, and leaks my browsing history to the search company even if my browser is supposedly "private" or "incognito". But it does make me dependent on URLs following a standard pattern.
If you prefer to ignore my suggestion that's totally understandable. Obviously I can always just go to ghostbsd.org and then select the forums from the navigation menu - I try to avoid doing this when browsing, as an unnecessary page load plus fiddling around in a menu is usually slower than just typing the URL I want (provided I can guess/remember it!), but it's not the worst thing in the world :-)
For what it's worth, freebsd.org is even "worse" in organisation in that sense. There are some URLs like freebsd.org/about and freebsd.org/news but it's not just the forums which are missing, it's also things like freebsd.org/download and even freebsd.org/donate - which is a terrible omission. Particularly when they do have some redirects set up, eg freebsd.org/handbook goes to docs.freebsd.org/en/books/handbook/ like you'd hope. So they do use redirects, just inconsistently. The ghostbsd.org site is much simpler and more logically laid out, and I think it's only the forums whose URL is inconsistent (though some menu links, like the docs, go off-site) so the only change I'm suggesting. Have no fear, I fully intend to write an even more long-winded and annoying suggestion to the freebsd.org maintainers at some point :-)))