Like every other modern usage of the ‘S’ word as in smart meters, smart motorways, I have come to simply equate the word ‘smart’ with ‘hidden agenda’ and ‘treat with caution and suspicion’.
In the case of Smart TVs I suspect, the hidden agenda is mainly one of increasing product sales, by inducing early obsolescence. Plus of course, mutual back scratching trade deals. I’ve no doubt for example that Panasonic get paid a few bucks by Netflix, every time they ship a TV with a ‘Netflix’ button on the remote.