No, it's more that the schools grant the collection of their media rights money to the conference. That's why when the Big 12 or Big 10 announces how much they distribute, it's coming from the conference.
So let's say Clemson leaves, and joins the SEC. The Clemson portion of their SEC payout would be delivered to the ACC to be distributed to members of the ACC, since the ACC owns Clemson's media rights until the expiration of the deal. Ergo, the ACC would be thrilled if Clemson left for the SEC right now, because they'd get that 100 million, and they wouldn't even need to pay Clemson out of that money.
That's why UT and OU are still in the conference.