Generalizations can be accurate with individual cases being exceptions. So the presumption doesn't fail based on your one case, same as my individual case (also not being more well-to-do) doesn't disprove the accuracy of the generalization. And I think it is safe to say that most jazz vinyl collectors skew older and more well-to-do. I would hope that that isn't always the case.
I think your second point has an embedded really important point. Younger, not-wealthy buyers need to see some less expensive releases in order to buy the vinyl, so that there will be a future for jazz. Here in Los Angeles (big city), there are solid crowds for experimental and improvised music (and very small audiences as well), but I don't know if many of those people are looking at buying jazz from the 1940s-80s, and at $30 or $40 a record, they aren't likely to pick any up on a lark.
Limited edition high-cost box sets from New Land (last year's Dorothy Ashby, and now this) aren't really going to be the primary practice of the industry; these are exceptions, and may or may not find enough buyers at that price point. It costs a lot to do all the work for a nice box set - restoration, paying for essays, licensing images & music, pressing records, storage, paying personnel to administer, assembly, shipping etc for a product that will never have mass sales. And their break-even point needs to be somewhere below selling all 1000 copies. I mean, I won't buy it, and they probably won't sell all 1000. Would they sell them all if they priced it at $100? $75? That doesn't seem likely either. Might as well price it high, so they can break even after selling X number (200? 300?)