I can accept that excessive use of entertainment devices is probably not great for young kids. Excessive use is the key though, and there's not nearly enough research to quantify that to the degree required for legislation.
I'm very skeptical of blatantly unenforceable nanny-statism like this. Doubly so where it involves parenting decisions that aren't conclusively detrimental. But cheerleading for it is even worse!
As for railing against the nanny-state - give it a rest. Most people are not experts in everything and expert advice, say, from the AAP, should be heeded.
Did you read the article? They have banned iPads for children under 2 in Taiwan. There is a gulf of difference between expert advice and legislation.
Red meat being bad for you was common sense. Fatty foods being bad for you was common sense. Asbestos being safe was common sense. Hell I saw a guy eat it to prove it was such.
Bright colored Snakes being dangerous is common sense. Something like this isn't common sense. It's parenting by government via criminalization. That's crazy. And we're not even talking about real child abuse.
Fatty foods were a part of our diet and then the experts at time said they were unhealthy and provided evidence - still the burden of proof was on them.
Children were (successfully) raised for generations without digital devices - you need to actually prove it's a benefit otherwise it's wise to avoid it just on being conservative.
A couple of days ago there was an article about parents camping out for days to get their kids registered for a specific school.
If all experts (like teachers) are so good, why are parents going to that extreme length to avoid the majority of those experts (teachers at the unpopular schools)?
If you have kids, you will find a lot of crappy opinions handed out to you. Another example would be "the worlds worst mom" who was criticized for letting her 9 year old kid ride the New York subway alone. Which expert would you as a parent trust?
Enforceability is not necessarily a criterion for the usefulness of the law. It only is in western states with an emphasis on individualism so our skepticism comes from our own cultural background.