financially self-sufficient - not whether they can keep up with the highest levels of NCAA. Maybe those two concepts are intertwined. But if there is a break-off between the top level NCAA schools and a second tier, and BYU could keep afloat in the second tier and remain financially self-sufficient, I see no reason why the BOT is going to pull the plug just because they are in division 2 (a future d 2 formed of G5 schools) instead of in division 1.
Maybe donors are going to lose interest in such a D2. But that would remain to be seen.