With the second-generation, Apple is considering shipping custom-built Vision Pro headsets with preinstalled prescription lenses directly from the factory. Gurman notes that this invokes a different set of problems with sharing a headset, reselling it, and when a user's optical prescription changes over time.
I've mostly stopped paying attention to Gurman and "considering" is a weasel word that means essentially nothing at this stage of development--I'm sure people on the team are
considering any number of things that are wildly impractical, technological infeasible, or just bad ideas, and will never even make it to the prototype stage.
But to address this directly: It's an obviously stupid idea. Even as an adult, my glasses prescription shifts gradually and I need new glasses periodically, not to mention there are two people in my household who would use the thing, both of whom wear glasses with wildly different prescriptions.
If this were an inexpensive "single user" device like a watch,
and something that users were likely to upgrade on a regular cycle like Airpods,
maybe you could get away with it being factory-configured to a single person. Even that's a stretch, though--the Apple Watch at the low end is relatively "cheap" and even the AirPods probably have at least a 2-3 year upgrade cycle and eartips that are easily replaceable in the box.
The Vision is of course neither of those things--even if it was cheaper, it will (or should) have a computer-like upgrade cycle, and there are all kinds of reasons to want to share one around a household. And this would destroy resale value, which is a critical component of ownership, particularly at the high end--one of the reasons a lot of people are able to upgrade iPhones and Macs regularly is that they can sell or trade-in the old one for a pretty decent chunk of the cost of the new one. A $1000 subsidy on a high-end Mac upgrade 5 years after buying the previous one is not trivial.
Even the factory-replaceable lenses are a huge downside, because you have to buy one for other family members, and it flat-out kills letting a friend use it if they have glasses, not to mention wrecks sharing one or a few headsets among coworkers in a business setting. A friend of mine was able to say "here, check out this cool VR headset I got", because it fit over glasses and I could just try it. If I get one, I won't even be able to give my glasses-wearing friends a test-drive--so much for word-of-mouth advertising.
I'm still seriously considering getting one, but the expensive prescription lenses are a big hit against it, and if a future version were to have factory-installed prescription lenses, I wouldn't even consider it.