In thinking about this, I think I see a method to the madness regarding the premium attraction up-charge that isn't just profit.
... Possibly.
As was previously, it wasn't uncommon for all the most desirable attractions to be fully booked before the end of day at the 60 day mark. Part of this was due to people getting up at the crack of dawn to secure it and part of it was due to people being able to gain access earlier than 60 days by booking days towards the end of their trips at the start of their trip windows - sometimes a lot earlier for those people with long stays.
This was great for those folks with experience in the system but was probably a horrible experience for first-time guests who didn't know about the daily virtual running-of-the-bulls as well as anyone booking a more spontaneous trip already within the 60 day window, APs and day-guests who were limited to 30 days and basically, never got a crack at it.
For attractions that are brand new, this might be okay but six years after 7 Dwarfs Mine Train opened, this was still a thing.
Under the new system, the people who worked the old system have lost their advantage but in so doing, the playing field is now level.
Everyone can opt to pay the fee to ride FOP now, if they really want to get ahead of the line but presumably, due to the cost, many will not.
Unlike the $15 program where capacity reserved for lightning booking will probably need to continue to be a big percentage, for these one-offs, especially with variable pricing, there is the potential for a huge drop-off.
This means that at various points in the day, if 70%+ capacity isn't being used for fast-pass, the standby line, which I assume will now just be called "the line" should move a lot more briskly.
There will be more people in it but now with everyone in that line, the average wait time FOR THAT LINE should go down, helped by not just having most people using that line rather than the fastpass line but also with the loss of people like our "I never wait more than 25 minutes for anything" folks who are now out of the equation - unless they change their stance, that is.
I'm sure these lines will continue to be long but there is the potential for them to be a good deal shorter than in the past and the common situation of standing around so much with no movement should be vastly improved.
This is of course, contingent on that pricing being such that it dissuades the majority from doing it.
For things like ROTR, this won't improve anything for a long time but if you've done 7DMT every trip for the last half decade or more and the same with FOP and many of the other premium experiences that you were able to book at 60+ days out, is it going to to be worth it to you to spend $20+ per person in your party to do them on this trip with the line skip vs standing in a line that is potentially shorter (in wait time if not length) than it's ever been?
I can see people being willing to splurge once to do something they've never done before (one of the reasons this won't help much with ROTR) but I can't see too many people shelling out for every "premium" experience every day of their trip the way people who were maximizing their advantage in the old system obviously did.
Not saying it'll work out this way or that Disney won't decide to optimize for profit rather than guest satisfaction when it comes to pricing and capacity reserve (making it so a whole bunch of people will see it as cheap enough) and honestly, if I was a betting man, I'd say my faith in them is low but since we're all just guessing at this point, the separation of "premium" popular attractions from the pack could actually be an attempt to solve some of the standby problems by acknowledging that their capacity is too low for their popularity to have either the old system or the $15 system effectively work at keeping the majority of guests happy.