I believe there is too much red tape from the phone calls I have been on again and again. They don't want to get into legal trouble with AMC (American Movie Classics) which is shown in High Definition. AMC being a direct competitor of TCM. There is no way in 2019 that TCM only offers SD to Verizon.
They have space to add a channel, but Verizon Fios On Demand has contracts with AMC to get their titles. Some kind of shady deal going on. I'm still using Verizon but when my contract ends I may switch back to Comcast after all these years. Honestly TCM was one of the greatest networks I've ever watched in my life. You learn a lot about movie history, and it's a shame they can't come to an agreement. Comcast also has CPSAN in HD, which FIOS is missing as well.