The more I think about it, the more I'm against Iowa State.
It's one thing to look at ISU's increase in enrollment, their football success, their fan appreciation, etc.
And if they get a seat at the big conference table, 20 years later we can look back and say "clearly they were power conference material".
But what happens if nobody picks them up? They end up joining a G5 conference, and then the recruiting falters because local Iowa kids want to play in the B1G on television instead of the G5. Iowa gets better because they're no longer splitting the state's top recruits, so they become more competitive in the B1G.
I don't think Iowa State really moves the needle in any way for the conference, and letting them fall to G5 oblivion arguably makes the conference stronger by making Iowa stronger.