And unless all G5 teams can earn their way into the conference, there's no way they would agree to that. Would that conference get the bid most years? Yes. But that's not how you improve recruiting. Its much easier to sell "We are a Power Conference because our champion is guaranteed a NY6 bowl" vs "We are the best G5 Conference because our champ usually goes to a NY6 bowl."
Additionally, by opening up the conference and allocating the funds to those programs, it incentivizes schools to invest because there is a real monetary reward for investing in your program. Eventually the cream will rise to the top and the conference will be made up entirely of programs with invested fan bases and Power conference level facilities.