I would agree with you on the majority of the restaurants. However, I would say there are certain exceptions such as Victoria & Alberts or Bistro de Paris or California Grill. I think you can consider V&A a "special event" , wouldn't you? I do not think it's unreasonable to make a reservation for a signature restaurant in advance.
For those that are making dining in the park their secondary or tertiary focus they can work within the confides of the system and go with whatever services are available. If they feel they are entitled to a sit-down meal and don't want to play within the rules of 180 days out they have choices. They can go such as Tony's Town, Biergarten, Teppan Edo, La Hacienda de San Angel , Restaurant Marrakesh or countless others. All of which mind you I can get a reservation for for the first week of October.
Yes, I agree that some of the high end restaurants (or even some character meals) fall into the "special event" category even at WDW. And I know that there is usual always availability at some TS restaurants. However, the best availability is in general at the resort restaurants which are difficult to reach for those who trust Disney with all their transportation needs and in theme park availability is limited. Actually, I like eating at the resorts, so it is not an issue for me personally. I have just overheard conversations quite often on the busses or in lines about how difficult it is to find someplace to eat as there are plenty of people who don't expect that restaurants sell out so much.
And interestingly, I was just recently at DLP and when I enquired one afternoon at a restaurant whether they still had reservations available that evening, I was not only told that they could give me one for an early dinner (they were booked for the later times) - or I could just line up for a table as they leave tables open for walk ins.