This is the current state of affairs. And it is so impactful that when these people are given a laptop for the first time, they try to swipe up on the screen. They don't know how to type on a full size keyboard ...they know how to swype-type.

In fact, Indian search traffic is heavily leaning towards voice typing (and we are already the world top 3 bandwidth consumers)

India is the first market where Netflix has a smartphone-only plan.

So yes, the world will change dramatically in thw next 50 years - but that's why the next evolution of computing devices will be foldables and the like. The laptop based interaction will be restricted to developers and the like.

The keynote of Android Dev summit (happening right now) started with foldables. They are making this a key part of the developer push as the next upcoming haptic interface.

Sure, all that makes sense, 'the only computing device they will ever own in their life is a smart phone' is simply not accurate, though.

What you really mean is that the only computing device they have owned so far is a smart phone.

You can't claim that in multiple decades smartphones will be the dominant computing platform. It could be anything; AR goggles, brain implants, hell, we could have gone back to the stone age and be mucking about with abaci. ;)