Sorry, but installing arch linux doesn't mean you are some computer master. You are just following instruction on a wiki. Anyone could install arch linux if felt like, and wanted to put some time into it.
Some people make arch linux their personality especially the forum.
The initial install isn't usually too bad for the most part, it's extensively covered through both the arch wiki and the myriad youtube install tutorials. I believe there's actually a pretty robust install script for arch now as well, which helps to make it a bit more accessible.
It's after you've installed arch and begin to configure the system yourself such that you come across some issues that are a bit more off the beaten track that you realise how unfriendly and elitist the arch community can be. As you mentioned, the forum is usually especially bad and every thread begins with the op having to try and explain to a gang of ravenous arch nerds that they have in fact read through the relevant wiki page, and that the wiki page does not in fact solve any of their problems.
I think if it weren't for the fact that I've already got my arch system set up nicely, and for the godsend that is the arch user repository, I would've switched to another distro a long time ago.