It isn't the invasiveness of glass that is the trouble. It's the minimum focal length of the eye and the speed of focusing. I want an overlay that is in focus, not to read email while I'm walking my buddy's dog.
Once glass is directly on the optic nerve things will be better.
Unless there's a big advance in magnetic field manipulation, I doubt it.
Basically - unless we find a way to inject data non-invasively using an advanced version of transcranial magnetic stimuation.
The basic problem with bioscience - in fact anything that's not computer science, is you can't just hit "recompile" when you screw up. We can't just replace an optic nerve that goes bad, in fact anytime you do even minor surgery you run the risk of an infection that wipes out whole systems of the body from a tiny mistake.
Once glass is directly on the optic nerve things will be better.