The price of tickets has definitely had an affect on crowds. However, this was by design by Disney. They heard the complaints about crowds being too large and went to demand pricing to help lower those crowds.
However, I also think you are understating the affect of the new attractions coming. Its not just Star Wars. Disney is investing something like $2 billion into Walt Disney World between now and 2021, with the majority of the items being built slated to come online by the end of 2019. Isn't it safe to assume that if I am in that slice between fanatics and non-fans, those that go only once in a lifetime or once every 4-5 years, and having heard the news about all that is coming, that I would feel my $100 is going to get me a lot more bang for my buck in 2 years than it is now, so I am going to put off my trip for two years. Hell, people are standing in line for more than 5 hours to ride the new Pandora rides (and its safe to say most people aren't die-hard Avatar fans). Its safe to say plenty of people are already planning their trips for Star Wars, and not just Disney fans.
I think the point that is being overlooked, which Ph pointed out, is that its not just the general Disney fan that is saying people are putting off their trips. In fact, surveys have shown people are putting off their trips until the new items come online. What myself and Ph and the other Disney fans are doing is just repeating the results of these surveys, not giving our opinion.