There's already evidence of this. A couple months back, the SEC openly declared they would invite two more members if they could cover their full shares of media revenue.
LINK And to my knowledge, nothing ensued in the way of any response from ESPN.
Of course, you can read various things into that. Normally, developments like these are kept under lock and key until finalized. Why would the SEC need to leak the content of private negotiations to the media if they were receiving mutual interest from ESPN? And unless anyone heard otherwise, there was no response to this "news" from ESPN.
The big conferences have nothing to fear as far as outside attacks. Greed is what motivates them beyond a point of economic efficiency. That and they don't want to get into the more relevant issue of their own internal (in)equity, why/how a school like Vanderbilt receives the same share as Alabama and now Texas. None of that of course makes sense.
Hand wringers in this space--and there are many--take these developments as some sort of beginning of the end. True to form, I see very little of it that way...