Maybe there is no legal standard for what a technical garment or fabric is, but I take it to mean that it uses something recently developed as opposed to doing things the old way. Like so many buzzwords and standards, if it hasn't been abused yet, it will be, but that doesn't mean it's entirely meaningless.

My wife and mother in law were in an outdoor clothing store, and my mother in law said she wanted to buy stuff for both of us. I tried on some pants made by Prana (or really, they call themselves prAna). I had never heard of them. Mother in law said they looked good on me, so I let her buy them. At $80, I wouldn't have bought them for myself. And wow, I'm impressed. They are stretchy and comfortable, and I can wear them riding in the rain with more comfort than any other pants. They are warm enough in cold weather, yet they are also cool enough in warm weather, so I guess that means we can call them breathable. So I'd say there's some kind of innovation going on. I don't follow the textiles industry, but I'd say they're doing stuff, just as so many industries are not done innovating.

prAna men's pants at REI