Yeah, sadly from a economic perspective it is kind of obvious how a continuous source of revenue might be more appealing compared to a one time purchase. Especially with a product like TVs that usually have a pretty long lifetime before being replaced.
Although i would point out that (at least in our current society) privacy and an ad-free experience in many ways is treated as a luxury good. Persumably a TV with a better OS would be sold at a higher price, and confronted with this choice many consumers would likely choose the cheaper one.