Instead of doing Max Pass, Disney could just do away with the advanced reservation portion of FP+, which would make it pretty much the same. However, such a move couldn't be a spin to make money, which is why we're having this discussion. The only real difference at that point would be Photo Pass, unless I'm forgetting something.
Even now, after you use your three fastpasses, you can get more, which works very similar to Max Pass. The only thing is, the choice is limited due to the better options being occupied by advanced reservations. Take that away and there's not a lot different other than one costs money and the other is free with admission.
That said, DL still offers the old FP, which I believe is extinct in FL. DL would probably see complaints rise if they ever cut legacy FP entirely and tried to force people to pay for Max Pass. It's an interesting thing to look at, IMO, since no way would they haul those machines back out in FL. They do have the kiosks still, but could you imagine the lines? I suppose that's what would happen though.