Don't get me wrong, Apple could do this if they wanted to but it is the sort of hard gruntwork boring, almost pointless tweaking to globalise products that I think they wouldn't do. They would just give you a TV that could access sufficient IP services to be valuable rather than dilute the experience by handling broadcast.
Many people already do not connect their TV to a broadcast signal, especially in the US but in many other areas where STB based pay TV is common. It might not be as much of a showstopper as you think and if anyone can get away with it Apple can.