Plenty of people do. I do. You make it a habit so it's not something you even think about. Or put another way, it's like brushing your teeth--it's something you do because not doing it makes you uncomfortable. (And as someone who had to develop the habit of brushing as an adult rather than being trained as a young child by attentive parents, I know it's possible to develop such habits belatedly.)
I've found that in modern cars the B pillars are so far forward and wide that the value of the blind spot check is diminished. In my 2018 mid-sized SUV I have to stretch so far to see the blind spot that in heavy freeway traffic I feel like I'm taking my eyes off the road ahead for too far long. So I'm on the fence on the turning the head thing and suspect some day soon pervasive collision avoidance systems will definitively settle the matter, though I'm not sure I'll ever be able to break the habit myself.
But it's definitely a mistake to think that it's not practical to consistently do something as simple as checking your blind spot. It's perhaps one of the few driving tasks that one can reasonably expect to perform with near perfect consistency, even during emergency situations like when you're tempted to veer to avoid a rapidly approaching road hazard.
