Problem with Smart TVs is they become obsolete super fast software wise. And basically, unsafe to connect to the internet in a few years.
Most TVs have CI+ ports. I can easily imagine an upgradable "smart module". Just buy a new compatible one (which, effectively could just connect for power and HDMI) and get the brand new stuff.
There is no bubble, smart TVs are a consumerist trap and it will require government intervention to fix because nobody has any incentives otherwise.