A very stimulating environment isn't what a kid always needs. Quite apart from inter-kid differences, the downtime is just as important. My kid got a lot from just being carried around (or later following us around) while we continuously narrated what we were doing (laundry: look here, we match up the socks by colour; cooking: watch out this knife is very sharp but see how the carrots come apart). So net not a huge increase in time.

BUT kids are super exhausting and demanding and if you are worn out you won't be able to help them much either. I tried not to bring up my kid the way you describe, but I have to say there were plenty of times when I did the equivalent (no iPads or TVs in our case but essentially much the same). He came out fine.

There is no perfect system and what works for one doesn't necessarily work for someone else.