[T]he reason why older people don't use the technologies is because they suck, are intrusive, unreliable and fleeting.
This. I was born in the 1950s, when dirt was still relatively new, and this is exactly it. When one first sees new software and UI technologies as a young person, understanding them is an end in itself. After 50 years of watching them come and go, however, I am tired of the technology of the month, and instead find myself using something stable that will allow me to get my "real" work done -- that being the point of software, after all.
Learning to use a good software tool once is a useful and rewarding experience. Being condemned to a lifetime of re-learning to use the same tool every year just because some idiot changed the UI, not so much. (Sisyphus would understand.)
I sometimes ask these UI wizards what they think would happen if I moved the keys on their keyboards around with every software release, in response to the latest theories on typing speed and accuracy, and perhaps added and/or subtracted a few just, well, just because I thought it would be a good idea. If one is, say, ten years old and just learning to touch-type, perhaps the new keyboard layout indeed would be better. However, the installed base of zillions of users that are used to, and expected to see, the old keyboard arrangement would be totally hosed, and would need to retrain themselves just to get back to the productivity levels they had before I "helped" them. Do you really, really want to do this kind of thing to your customers? Repetitively?
I am always amused to find that the same programmers that gleefully shuffle, delete, and obfuscate menus and other UI features for their users strenuously object if you even suggest taking away their precious Dvorak, XP, or simple QWERTY keyboards -- let alone, say, reverse the order of the bottom row of keys, transpose the T and H keys, and move the "@" symbol so that it is now CTRL - ALT - ].