Huh. Is that true for other retro components? Not something I need, but I heard basically all PSVitas and Memory Cards were gone.
A few years ago (~2020) you could get a brand new PS Vita in the color of your choice for around 12,000 yen, of course this was back when the yen was strong so that was around $120.
You aren't going to find that anymore. So from that perspective they are "gone." There are some listings for new ones but this far out it's likely it's just a very, very nice condition used one someone has put back in the box.
Now you can expect to pay 15,000 to 20,000 yen for a used one, depending on color and condition, which in today's exchange rate is $95 to $126. This isn't particularly expensive IMO, it's just not what it used to be. It's not like they are unavailable.
What's actually shocking is what has happened to SNES and Game Boy prices. Most stuff is 10x what I paid last decade.... but at the time PC Engine and desirable SHMUPS were 10x what people had paid a few years prior, if you put it into perspective you have to remember that there's a time aspect to all this stuff. At some point in time PS3 and Xbox 360 games will be valuable, right now they cost nothing.
At higher capacities, the Vita Memory cards get unreliable to use and unreasonably expensive, it's better to mod the console and use SD cards instead.
I guess if you really want to use physical copies on a 2000 I can see the appeal but yeah it's not a good buy these days.
A 64GB card has always been expensive, at a glance they cost less used than what I paid to get one new in person in 2014.
Edit: another thing that's changed is in-person shopping. It used to be you could go to a junk shop (it's like a thrift shop pawn shop combo) in the suburbs of Tokyo and clean up with cheap purchases. Nowadays all those shops "know what they have" and the vintage video game hardware and games are all priced accordingly. But even that was a big change from let's say 2008 where you could go to one street in Akiba and buy everything for 100 yen.
It's easy to think the glory days are gone but there's always something that's a bargain compared to a few years from now. AFAIK Wiis are still worthless.