This was definitely still taught in my public high school in the 2010s - if they stopped teaching this, it was very recently.
Granted, the teacher that tried to teach me this had no understanding of it themselves and would incorrectly mark answers wrong when they had the correct number of significant digits, so it was pretty botched in my case. Still was attempted in the curriculum though.
I have also found this to be the case. I can easily sit down and read something enjoyable for hours on end, but I try to watch a movie and within 20 minutes I'm wishing I was anywhere else. TV shows inhabit a kind of middle ground between the two, they're still tolerable but I find myself enjoying them less over time.
I can't say I really regret this change, I haven't noticed any real downsides. There's too much content and not enough time these days.
Granted, the teacher that tried to teach me this had no understanding of it themselves and would incorrectly mark answers wrong when they had the correct number of significant digits, so it was pretty botched in my case. Still was attempted in the curriculum though.