The Switch has had the same problem, which causes me to basically never keep AAA games installed for long, but they are still quite successful.
The Switch also tops out at 64GB with the new OLED model, whereas that's the starting point for the Steam Deck. There is also a history of consoles being offered with a wide variety of different storage sizes (Xbox 360), and I don't remember that causing any serious problems for them (if you ignore the humongous size of the Xbox dashboard at the end of its lifetime, which is an avoidable problem).
One caveat, at least for me, is that Switch games tend to be designed around cartridge limits, and the transfer speed there isn't too much faster than the Switch's UHS-I SD card reader (although I can't find any tests or specifications on the cartridge port). PC games nowadays tend to be designed around either a SATA-III SSD or a PCI-E SSD (over NVMe), which will be much, much faster than a UHS-I port, so PC games over an SD card won't be anywhere near as performant as a Switch game.
The Switch also tops out at 64GB with the new OLED model, whereas that's the starting point for the Steam Deck. There is also a history of consoles being offered with a wide variety of different storage sizes (Xbox 360), and I don't remember that causing any serious problems for them (if you ignore the humongous size of the Xbox dashboard at the end of its lifetime, which is an avoidable problem).