Secondly, those of us who learned about IT by experience, rather than in an academic environment, tend to be far more broad-minded and less bigoted than those who spend five years in university, come out waving their silly little bits of paper around, convinced that they now know 100% of what there is to know about IT, and that they can go out and tell us who have been working in the industry for 30 years that we're doing it all wrong.
The best people have a diversified knowledge base. I certainly would agree that new graduates (of any technical discipline) need a little seasoning but after perhaps five years commercial experience they are much more rounded, they've picked up practical knowledge and experience of real situations and all the surrounding areas outside their original discipline - management, administration and record keeping etc etc. In contrast self taught and on-the-job learning is always something of an unknown quantity and remains like that throughout one's career - there are frequently huge areas of ignorance, a lack of investment in learning and if something works that is the end of story even if a different approach could have been cheaper, better, or less effort. Formal educations fills in many of those gaps, not always well enough to provide all the answers but enough to pose the right questions, the real issue more often than not.
There's also a question of investment - if you've spent three years at uni you have a hell of a lot of groundwork under your belt before you start tackling real world problems. Without that the temptation is always to cover the bare minimum to achieve the aim in hand even if a more sophisticated approach would be more profitable in the long run. I'm in physics myself (primarily astrometry techniques) and I see it all the time - people have gone to great effort to achieve something and do so badly which when you consider and immediately ask "Why didn't you use a ____?". Within IT I frequently see and hear of completely the wrong tools being used because it is the tool they know. For example there is a choice between spending a week hand-writing a huge, unmaintainable parser or investing a fortnight learning Lex & Yacc for no immediate benefit, but subsequently writing the same parser in a morning. The self-taught tend to take the first approach. The CS graduate has already taken the second.
Time and time again, I see people tell me that I'm wrong, because they are applying their basic, limited knowledge, to a situation that I have more advanced knowledge about. They are convinced that I am wrong, and once I engage them in conversation about it, they just start sprouting all sorts of erroneous cobblers, without realising how stupid they are making themselves look. Just a couple of days ago on this very forum, I had one idiot trying to tell me that read errors that have been detected by CRC checking are somehow responsible for silent data corruption. By very definition, that obviously cannot be true - that is what the CRC is there for. I have also been told that the bad144 utility reads the inbuilt defect map from a hard disk's controller. Errr, OK... Maybe in a parallel universe.
The tone of this immediately put me off, it reads as "I'm so much better than everyone else here, the way my skills developed is the One True Path and anything else is wrong." You cannot present a logical argument that you are enriching yourself by denying yourself avenues of learning. There are many sources of skills and knowledge - academic education, industry certification courses, reading and private study, practical commercial experience, pet projects, discussions with your peers, even media reporting. The truly skilled individual has and does expose themselves to as many of them as possible. Stating at the outset that you are not going to consider one of the principle sources, and then treating those around you with contempt because you consider them to be beneath you is impoverishing your sources of skills and learning. That is ultimately to your detriment rather than your benefit.
Out of interest I did look through your posting history to find the discussion to which you refer. If I called it I would say that you actually lost the argument. You made an initial claim which was challenged with a chain of reasoning showing that in the common case what you said didn't apply. You introduced a lot of smoke and mirrors and arguments based on the rarer cases but at no point did you defend your original claim against the argument against it. Therefore you lost by default.
What have you learned from that? Nothing, because they are trolls and unfit to untie your shoelaces. That is not the approach of someone who learns wherever they can as an investment in the future.