How young is too young for a kid to have a tablet?

Here's the deal... One in FOUR kids under two has a tablet.  As in, their own.  Two seems young but not in 2018, start em' young! More than a third of 3 to 5-year-olds have their own tablet as well.  As long as they're LEARNING at age 2 and not watching useless Youtube videos, I think it's great!