Sort of, it's probably not that simple. There's a bunch of nuanced impacts that will happen.
The old way, at one extreme, a park hopper with a pass not to MK could have made 1 LL for 2:00 at 7:00 AM. Then, again at 10:00, 12:00, and 2:00. That's 3 LL reserved before they could be there and 4 by 2:00. All for return times after 2:00.
For the person who was in the park already that's 3 slots removed from inventory that they never had any access to at all. Even if they made selections at the exact same times.
With the change, the hopper cannot reserve those slots at MK. This leaves them 2 options. First, wait for something to get to after 2:00 and reserve it, then wait 2 hours and repeat. That pattern is likely to delay selections that they only get 1 or 2, certainly nothing at 7:00 AM, deferring when they make each selection. Second, they reserve something at the park they're at for use closer to the time they're reserving it. That will shift load into the park they're in. However, the park pass is already managing crowd size and distribution in the early hours.
The implications and how it impacts overall experience will likely not be known until it's been done this way long enough to observe it.
I think this is most of it.
I think the 2 hour window is a hedge in the system because of popular rides that have return times much later. This is like when your third FP+ was late in the day and you couldn't take advantage of getting a fourth until you used it. The 2 hour window makes that experience better.
But, what Disney clearly wants people to do is take a LL that's much closer than that. Something in the 40 to 75 minutes from when you're reserving it. Then, immediately repeat after you use it. If you did that, instead of 4 LL by 2:00, it could be 7:00, 8:30, 9:30, 10:30, 11:30, 12:30, 1:30, 2:30. Getting 8 LL in the same timeframe.
The issue is, for the popular rides, that's almost impossible. For the other rides, it works just fine.
