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 Switc

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.