Ironically, as ticket prices have soared in recent years, the parks have gotten more and more crowded. I remember a time when there really was a proper off season. Now, I maybe experience a few slow days each year. It seems as though Disney has very cleverly engineered a number of special events during the off season that trigger increased crowds. Some examples include Lunar New Year, The Food and Wine Festival, and a number of special ticketed events. This past week should have been a slow week, but the park was relatively crowded on Tuesday and Thursday when I was there.
The OC Register recently had an article on this phenomenon of increased crowds despite skyrocketing ticket prices. Apparently, people are more interested in spending money on recreation, tourism, and entertainment these days. It's the experience they want, so they will spend money not that rather than buying things.
My theory is this: There are a lot of young people who cannot afford a week long vacation, but they can afford a yearly pass to Disneyland. It is kind of like taking a series of short one-day vacations throughout the year, instead of a single vacation. Although Disneyland does not advertise the number of pass holders, reliable sources say there are roughly 1 million of them, and that is only for the Disneyland Resort in California. Most of them are local, but not all.
My pass does not expire until October, but I will end up paying about $50 more for it (and a little more for parking, I think). It's still worth it to me, but there have been many days when the crowds are so awful, that I can't even imagine someone would pay the price of a one-day ticket for that experience. Makes me glad to be a pass holder who can come and go as I please, and not worry about cramming it all in in a single day.
Edited to add: I forgot to post think link to the newspaper article: https://www.ocregister.com/2020/02/14/bubble-watch-disneyland-admission-hikes-look-frothy/