I think you are wrong about aTm in the Houston market. They brought the SEC Network to Texas, but I don't think the SEC Network is a tier 1 channel in Houston. Someone from that area would have to chime in to confirm.
As for the cutting the cord, I agree. I think you will see more networks go to a monthly pay app style network. Sling TV is the start to it. You get a few basic networks & you pay for additional packages, like the sports package, kids package or HBO.
This style will also make the conferences look less at markets they are in & more for the prestige factor of a team. Making big name teams more valuable then the market they are in.