Look, I have absolutely no hate against the Vita, I think its a great device.
But this comparison is ludicrous.
A steam deck can emulate a PSP or Vita.
I know because I have one and I do this.
Was the SteamDeck guy a moron for thinking he could get away with playing Hogwarts Legacy for a 9 hour flight without it dying?
Yes.
But this is ludicrous to compare to a visual novel on a Vita.
Steamdeck dude easily could have made it the entire flight playing a visual novel.
Or... any emulated game from about the PS2 era backwards.
Or any modern 2D game. Or any modern isometric 2.5D game. Or probably any 3D game that isn't from the last 5 ish years...
... If rendered at the same resolution and settings jammed all the way down to the minimum, on par with Vita graphics.
Or he could have also undervolted his deck, used power save mode, turned off his WiFi, underclocked his GPU.
Almost all of that can be done from a menu that is accessible from a single button press.
If the dude had brought his actual proper steamdeck charger, yeah, airline chargering ports are often underpowered, but it would trickle charge enough that he could get away with a lot less optimizations / lower graphics settings, and survive a whole 8 or 9 hour flight.
I again know this because I've done it with an even shittier charging port on a fucking 24 hour Greyhound bus ride.
...
Yes, the steamdeck is a big beefy boy and doesn't fit in a pocket.
It isn't meant to.
There is little point in making such a small gaming device these days, basically outside of retro niche do it cuz you can startups (more on that below)... because most modern smart phones are powerful enough to do everything a Vita can do, if you set it up for emulation, or just natively play android games.
If this person has a modern smart phone, there have been many 3rd party basically controller mounts that plug in and surround a smart phone to turn it into basically a mini deck or mini switch/2... those have been around for almost a decade.
That is where all the development has been in basically pocket sized handheld gaming, for the last decade-ish: smartphones and accessories.
Remember everyone playing Pokemon Go?
Whatever gacha waifu battle simulator is currently in vogue?
That is the majority of the money making in gaming for the last 10ish years.
That is the majority of played video game hours on Earth, in the last 5 to 10 years.
The mobile gaming market is larger than literally every other platform combined, and then some.
...
But hey, if you are looking for a handheld, portable, pocket compatible device:
https://retrododo.com/best-retro-handhelds/
Here you go, there's a list of all the things you're looking for, a bunch of small, fairly recent startups who don't have marketing budgets so apparently the author has never heard of them.
...
If this person (author) wants to blame someone or something for the lack of standalone, portable, handheld gaming devices... tell them to look at how obscenely greedy and manipulative the entire mobile game market is, all using dark patterns and MTX to suck money out of mostly children and give them addictive personality disorders.
That's your culprit.
The author mentions having a VirtualBoy, so we can reasonably conclude they are in their 40s or nearing them, at least, and probably has just absolutely no idea that shitty cellphone games are not just common, but literally dominate the world wide video game market.
Out of touch.