You hear only bits & pieces because that's all they give. I agree with you that the intention is to resist SEC hegemony. (And maybe more important, ESPN hegemony) But simply scrapping divisions and making strategic schedules doesn't require an ongoing formal "Alliance."
I may be the only one who thinks so, but could the Alliance have monumental, industry-changing plans churning below the surface? I think most P-5 conferences are done with the NCAA. There will be a breakaway, and I think the next college athletics governing body will be a subsidiary of the for-profit "College Football Alliance"
Owned jointly by the conferences themselves, the corporation could establish lines of business for their own direct benefit rather that outsourcing to other parties: brokering NIL deals, in the same way a talent agency works; joint packaging of advertising to national advertisers; charter aircraft-sharing among conferences traveling to like destinations, centralized scheduling of competition to facilitate aircraft sharing or hotel booking.
The Alliance need not be restricted to "P-5" level conferences.
Another thorny issue on the horizon is the possibility that the courts will deem student-athletes as employees of the schools they represent. Administrators could save themselves enormous grief by designating "The Alliance" as their athlete employment agency, who would hire and pay the players, assigning those players, on contract, to the schools to whom they have committed. The players would, of course, be free to find their own agent/rep.
The oceans of cash flooding into college sports in the coming years will change things, mostly for the worse. But the smart administrators will find ways to harness the best parts of it and protect themselves and the athletes from the worst.