one

If you are near or far-signed, can that be used as a cue in VR? If you spend more than a certain amount of time (a lot? 50%?) not wearing your glasses, your brain is probably attuned to fuzziness correlates with distance. e.g. "This is in the range where your eyes are bad at focusing, so as an additional hint: here is how fuzzy this thing is"

two

Maybe your brain keeps up with eye position (the distance of where the "rays" from your two eyes intersect) and uses that information to tell the eyes how to focus.

If so, you could add a layer of realism by making things at the ray-intersection distance sharp and other things varying degrees of fuzzy.

Why wear your glasses? You can have 20/20 vision in VR.

three

Combining the two, what if you could upload your "glasses prescription" to a VR headset? Now ray-intersection distance can be used to add a small strategic amount of fuzzy for you, thereby more closely modeling how you see the world (with dialed-in fuzziness).