ESPN can find value in the AAC that they can't get from bloated P5 contracts. ESPN can better afford maintaining the status quo if the AAC provides bigger returns. The only way the AAC can do more for everyone is to legitimize it and then underpay it, say $8,000,000 per year, per school.
So, the AAC schools have enough cash to compete for right now, the current P5 conferences keep their gravy train and ESPN draws way more eyeballs to the AAC. When current contracts expire, another reshuffle happens. If it isn't feasible, it isn't feasible. However, that USF/UCF game had to have had wheels turning. The American has produced great late season games each year. Those games look legit, not G5.