What statistics are saying that attendance has been rising? 2016 saw a drop in all 4 Disney World parks by 0.5 - 0.7%. Yes, 2017 saw a less than 2% rise, but that is standard market correction for a year that a park debuted a new land. Want to hear something amazing? In 1971, when Disney World opened, the Magic Kingdom saw 20.49 million in attendance that year. Guess how many in 2016? 20.4 million in attendance. Attendance is not growing out of control. It's intentional decisions made by those in "control" to cause guests to have less time enjoying free rides and spending more time throwing their money away on overpriced food and souvenirs. It just seems more crowded in the parks because the fastpass system means some people spend very little time waiting in line and just wander around the park, clogging the pathways. It makes it seem more crowded.
Now that they are ticking off the people who frequent the parks you might see attendance drop even further below opening year figures. But where it will really hurt is when the frequent visitors who love the "Disney Bubble" no longer see the "magic" in staying on-site and get rooms elsewhere...like I will be doing.