From an ars technica review of the steam deck "friends", a portable device that is way ahead of the actual steam deck, specs wise, but since it runs plain unmodified windows is a pain in the ass to use as a portable :)

https://www.lenovo.com/us/en/p/handheld/legion-go-s/83n6000g...

there's an actual sku of one lenovo handheld that officially runs SteamOS, i assume that's what GP is referring to