You say that you "find it very hard to believe a family of 4 will have much use for the Vision Pro," and that will (initially at least) be correct. However the world consists of more than just toys for families of 4.
No family of 4 has a concrete saw, for instance, but every site contractor in a developed nation has several. No family of 4 has a CAD setup, or a transit, or a boom lift, etc., yet those things are all ubiquitous in the professional world.
IMO the AVP and spatial computing is very, very likely to become very relevant to professionals. Iinitailly at least, issues around toys for families of 4 are short-term not important. Long term, toys for families of 4 have been Apple's core moneymakers, but that does not mean that the world's largest tech supplier can not or should not also serve professionals. Even if AVP never appeals to families of 4, the space for AVP as a tool for professionals is solid. And some families of 4 have huge amounts of extra disposable income, so even that cohort of buyers may surprise us.
Note also IMO this AVP spatial computing thing is a long haul issue. Apple has lots of cash and need not see real commercial profitability for a long time, easily 5+ years if necessary.