"Is it likely that all rabbit ear TV will cease to be free? Or cease to even exist?"
If the current chairman is sincere about what he stated a few years back about carving up more UHF TV, it could hasten the end of OTA TV as we know it. They could potentially sell off one last chunk of spectrum and distribute out a few channels to the current lighthouse set up, which would mean you'd point your antenna at a few towers and get all of your stations from one market, or they sell off the remaining UHF spectrum and force stations to go to streaming unless they want to fight over the small VHF spectrum.
Congressional leaders met a few months back about utilizing more spectrum for 6G because you know we have to beat China. Who knows, maybe Carr might suggests carving up UHF TV because we need it so bad for keeping ahead in the mobile market dominance or something?