The problem is that at the point the FCC isn't enforcing things by fine, if you do set up a broadcast antenna, the stations (or as you aptly said, the conglomerates) can sue you for blocking their signal, because they have a contract that says they "own" those bands. And they'll sue you for loss of income, because if they sell less stuff by way of ads, they get less ads in the future, and then it's all downhill.

The big challenge is, most people now watch TV either through walled-garden streaming platforms (when was the last time you watched an IPTV or IceCast stream?), cable, or satellite.

Radio might have a hope if you can get it out there, but most of that has been captured by Spotify. It's an ongoing point of contention between my fiancee and me, because I like listening to terrestrial radio and believe that shortwave and HAM are the voices of the people, plus I listen to shoutcast / icecast "stations" regularly, and she pays for Spotify. I can't think of the last time she used the radio built into the infotainment deck in her car instead of beaming her phone to it.