I understand all of the above very, very well. However, based on your response, clearly, you don't understand how FP works and how it impacts the rest of the park's operations.
The long waits at TTA are directly related to FP despite the fact that there is no FP on this attraction.
What most people can't grasp is the concept of the virtual person vs the physical person with FP or any reservation based line system. For every FP you hold you essentially duplicate yourself. If you hold one FP you are two people, the physical and the virtual. If you hold two FP then you are three people, the physical and two virtual, etc.
If you hold a FP for Space Mountain, for example, then your virtual self is waiting in that line and theoretically, you're preventing others from riding. In practice, you prevent others from riding when you actually show up to redeem your FP. So while your virtual self is there, your physical self is off doing things like riding TTA or other rides or shopping or dining or watching a parade or standing on a walkway taking up space. If you had to actually wait in the line at Space Mountain then you wouldn't be eating up capacity on other rides like TTA and taking up space elsewhere in the park!
I'm not going to deny that attendance at MK is up because it is, but the real reason for massive overcrowding, long stand-by waits, and long lines at non-FP attractions is all because of FP+. The additional attendance averages out to about 8,220 extra people per day. That has an impact, but its nothing when compared to how FP+ impacts operations and crowding. When you take into account crowd flows, for example, not all guests will spend all day at the park then you really see that the additional attendance isn't much of a factor. There really isn't an additional 8,200 people in the park on average at every given operating hour.
One of the primary differences between Disneyland and Magic Kingdom is the fact that FP by design in California doesn't allow you to hold more than one at a time, unless the return time is more than 2 hours out and that's also assuming that you get another FP before the one you hold is valid. Nearly every guest walking into Magic Kingdom in the morning holds 3 FP's, which in theory means they are the equivalent of four people walking in the door, three virtual and one physical.
Also, don't infer that my comments imply that I hate FP. My opinion of the system varies. I see the benefits, but I also see the cons!