Hey doctorgori, thanks for posting. I've often thought about that over the years. I too got started in the early 90s, though never truly stepped away. I did however get out of actively "reef keeping" for a few years. On one hand, as already mentioned, keeping many of today's corals used to be a lesson in humility. I think it is amazing to be able to sustain a gallery tank, the more color the better. On the other hand, I have never actually attempted (now that it is possible) to maintain a region specific aquarium. I have always wanted to have two or three independent systems for the purpose of keeping solely inhabitants from the Red Sea, or the Carribean, or even a deepwater (NPS) softie tank for example.
I suppose for me, a "reef tank" simply describes a glass box with a stack of rocks and a diverse group of inhabitants including fish, corals, anemones, snails, crabs, bacteria, protists, pods, worms, and other various invertebrates. I think for someone who is trying to accurately recreate a slice of the reef in a living room, they should consider using organisms that would all be familliar with each other prior to getting in the aquarium (region specific). I am guilty myself, but I think it is funny to see fish swimming together in an aquarium that would not possibly have met in the wild.