And why shouldn't they? It's not much of a feat.
Back in the 1950s, it might have been a bit futuristic, what with door openers that only reacted to presence (pressure sensors), not to movement.
Back in the 1970s, it might have been a bit complicated, what with sensors that could track movement with ease, but with computing of movement paths slow and expensive.
Back in the 1990s, it might have been a bit expensive, with sensors and computers easily available but not trivially cheap.
Back in the 2010s, it was neither futuristic, complicated nor expensive. It simply wasn't needed.
But nobody needed cell phones, either. So why don't we have smart doors today? I could rig one with the right LEGO kit and a a hundred lines of code. But I don't want my doors to start thinking what I want.
Timo Saloniemi