While they may not be serving up much QAM, they'll still be selling TV to those who can't put up antennas -- even if it is just locals.
I see a future where the old-school carriers get into reselling pay OTT TV packages along with locals (not just a few of the locals but all the locals).
I see no future for in-home DVRs other than for OTA for those who can receive it. TiVo will wither and die. The only question is whether they extend a bit by figuring out how to wring something out of ATSC 3.0. Tablo may have a marginally better chance as I'm guessing that their business plan never contemplated pay TV recording. I see a lot of pressure coming from bigger companies with deeper pockets running more vanilla Android TV boxen (i.e. Amazon) in the OTA DVR marketplace.