it's not PfP and Xavier was never going to "sit out", and he never threatened to transfer. His team was going to maximize his NIL opportunities which were real NIL opportunities that did not include compensation for play or on field performance wherever that would have been, but wanted to stay at Texas if those opportunities were matched or bested.
You and many others are conflating things together. Just because the team/university/coaching staff benefit from a player being really happy about the NIL deals they are getting, and those deals being way bigger than they arguably should be and have more equivalence to pay for play contract values does not mean that they are pay for play or that any enforcement mechanism, language, expectation, anything is set in contract or even out of the contract to mean "pay for play". This leaves a ton of room for hurt feelings and a bunch of butthurt or whatever, but what it doesn't provide for is any room to say yeah fuck this I'm not gonna play football at this school anymore, because football has nothing to do with the contract or terms of the deal. If you choose not to play football because you are butthurt about the NIL deal you did or didn't get that makes you a fucking shithead, it doesn't make the collective a scammer, it doesn't make the coaches badguys, it doesn't make the university take responsibility for anything.
This is an extremely important distinction that you keep glazing over with your "handwaving" and magical "it's pfp, but not really in any way at all is it pfp". There is no "grey area" here, they aren't paid to play - full stop.
It's like arguing that PTA's are worthless and stupid and have nothing to do with a school being better/worse than other schools in the same ISD. The PTA is like an NIL deal. They can pay for better playground equipment, new paint for classrooms, all kinds of stuff that the district allows for them and it makes that school more desirable for their children to go to and for other children who want to transfer from other schools in the ISD to that one.
The NIL program at Texas is like the best fucking PTA in existence that maxes out spending on all the stuff that is allowable by state and local laws to make the school awesome outside of state, isd and federal funding.
Texas One Fund is a big reason why people like the entirety of their time at the University. It's not the reason they are at the University, but it could be a good reason to look at it because of everyone's raving about past experience and how it makes things just better overall.