For there to be no TCM you have to butterfly a lot of things, first there is no Ted Turner and his acquisition of MGM/UA and their film library before 1986, the pre 1950 AAP film library which includes Warner, Paramount studios and the RKO film library.
Then you need to stop the technological upgrade from coaxial cable to fiber optic and direct broadcast satellites systems that allowed for more channels to be received at home.
So if no TCM then there would have been something else that would have filled the void in the marketplace, maybe American Movie Classics stay commercial free.