If you don't want an internet enabled device, then you are looking in the wrong place. The I in IoT stands for internet.
That is a good question. I don't know. But I'd say it became a selling point after the internet became ubiquitous and reliable enough in the eyes of consumers. Otherwise people would be complaining about 'needs internet access to watch a movie/make a video call/play a game/push source code/order food/call a taxi/etc/etc/etc".