To be fair to the OP, prices at Disney have risen far, far faster than inflation, as a previous poster illustrated.
I remember when a room at the All Stars was about $69/night and a room at an offsite motel was about $50. Today, a room at the All Stars is about $150 and the offsite motel is still $50. Tickets, food, parking have all gotten more expensive at a faster rate than incomes have grown on average so it is true that across the board, Disney is less affordable than it was 10 or 20 or 30 years ago for the average family. For some, that might have priced them out, or, as Jes mentioned, made them go less often.
Personally, it hasn't priced us out but I can't deny that our trips, even though we do a lot of things to economize (drive down, stay offsite, eat many meals offsite, etc.), have gotten more expensive and suck up more of our income than they used to.