Dont you think electronic time for kids should be limited?

This is sort of 2 different questions. Of course time with electronics should be limited. But when it comes to your niece, are you sure you're in a position to know such specific details about how much time she spends doing this?

When you say she's on youtube for 10-12 hours, then yes this is obscene. And if her parents aren't paying attention to which videos she watches, it's downright dangerous. But you never said how you know all this for sure.

It doesn't matter what they're doing on the electronic device. It's NOT healthy. I'd say about 2 hours a day. Morning +night.

it depends.. what is it they're doing?

for myself growing up in the 'electronic age' my time wasn't limited.

thus, now i work in a corp as the owner and president in computerized technologies.

and i have a doctorates in computer sciences.

Although television can be unhealthy if watched too much, it can be educational as well. Of I were you, I would let her watch PBS kids.

It makes their eye contact much stronger.