And this will almost certainly be more expensive than plain old cellular. TV manufacturers would be covering a very niche market of people who have a TV in a location with no cellular coverage.
But I believe it's uneconomical more for licensing reasons than BOM reasons. Cellular baseband modems are an oligopoly, and so they attach all sorts of rev-share fees to use of their chips, beyond just the cost of the chip itself.
Apple actually owns the baseband/modem group they bought from Intel a couple of years ago. The 11 and 11 Pro were shipped with in-house ex-Intel modems. Since then they have moved back to Qualcomm but I have to imagine they're continuing development and will cut Qualcomm out one day. [1]
Yup, there are guides for how to open up your new TV and remove/disable the M2M modem inside. I don't think the cellular connection being in the sky will change too much about that.