> There's some chunk of society that isn't mentally tall enough to ride and messing with it will just frustrate them.

What kind of elitist nonsense is this? The reason AR isn't taking off isn't because the users aren't good enough for AR, it's because AR isn't good enough for the users.

> It takes time for new technologies to become widely adopted and utilized.

My point is some technologies just end up not being very useful, ever.

> while there's an IQ requirement of some kind for a person to understand and appreciate what's going on spatially with AR.

Could you expand on this, please? I didn't realise this was a significant concern until now.

Can a young child utilize AR on a handheld device? Maybe, although before a certain age 'y' the answer will typically be 'No'. That age y should tend to be more advanced than age 'x' when a typical young child would be able to utilize a picture, say of a cow or a chicken on the same handheld device. Spatial intelligence, IQ, having the full use of one or both hands, etc. are all part of the requirements that determine whether or not any given individual will be able to fully appreciate what's going on with AR on a handheld device. It's entirely possible that adults with different issues will be unable to satisfy these requirements and fully appreciate AR, which should in turn reduce the market for AR on handheld devices.