Only Electric Sheep Are Cheap: …sort of. Hydroponically grown food and meat out of the carniculture vats is cheaper, for example, yes. That’s what mass production is for.
But it’s not like anyone’s going to go broke buying a nat-steak dinner. Sure, people aren’t going to be eating nat-steak every night, but it’s not like a night out at the Natural Foods Restaurant (“Don’t Eat Vat!“, et. al.) now and again is going to be out of reach of anyone with, well, an income. Because the difference here isn’t that natural foods became more expensive due to environmental degradation, or whatever, it’s that vatfood became dirt cheap.
(Slight exception: well, okay, you can’t fit that many cows into a space station.)
Played straight in most other areas: after all, in near-post-scarcity economics, Baumol’s Cost Disease is in full play. Cornucopias can make pretty much anything made of common elements of regular matter for trivial amounts of money; people’s time, on the other hand, is expensive.
Which leads to counterintuitive results: diamond, for example, is a practically worthless structural material – and not even a good structural material, being too flammable – because even the simplest assemblers can produce arbitrarily large amounts of carbon-crystal in short order. Gold is cheap due to automated belt mining. Anyone can afford to parade around in diamond-encrusted cloth-of-gold pants. On the other hand, that hand-sewn, hand-embroidered shirt of what, to our eyes, are much humbler materials was orders of magnitude more expensive. Hand-made goods are practically the definition of luxury.