Msratty, I think your stating the obvious. Based upon the years I've been visiting Audiogon, I'm confident that despite the experience you might have had with your friend, the vast majority of Audiogoners are well aware of the importance of room considerations and system setup and the topic and been broached here many times for and by newbies and experienced audiophiles.
That you think that we don't is presumptious. Your posted atttitude about component matching is akin to going on a oenophile site and advising the members that, pouring most wines in most glasses will give them a buzz.
FWIW, most of my gear is over twenty years old, my system hasn't and typicaly doesn't change for years at a time. I frequent Audiogon to avail myself to other possibilities and I try to offer advise based upon my experience with some gear and systems, without presuming that everyone else here doesn't have a clue. I believe that for most, this forum is an aid towards the quest for the best sound one can achieve. For many this journey has many obstacles, including room, immediately available funds, etc., and yes, component matching. Like other hobbyist, some also like to compare items peculuar to the hobby, just for the "fun" of it. While I don't engage in that all that often, I can appreciate that none the less.
I suppose you could have opened this thread as a friendly reminder, but instead it reads (at least by me) as a contemptious diatribe.