I doubt those yogis work in STEM.
Not much need for sleep if all you do is meditate
Not much need for sleep if all you do is meditate
You might be more productive per minute after meditating but that's another discussion
However, in my experience it takes years before you may comfortably spend all day meditating. I'm pretty sure most of meditators, teachers or otherwise, are not able to do this. It's extremely demanding, it is only boring if you don't focus properly.
I've participated in retreats that start at 2h30AM and end at 00H00 every day, with 1h sits and 20m breaks in between (same routine over 3-7 weeks), and only a handful of people are able to follow this schedule. Even meditation "only" on a 9-5 schedule is hard.
For people doing it in their culture, from a young age, it's second nature...