Many have wondered whether installing games on SD cards will not slow uploads too much? Steam Deck installing games on SD cards
However, Valve’s Lawrence Yang dispelled all doubts, stating that the units tested by journalists, incidentally those of IGN, had the games installed on SD cards.
Yang: ” Sure, games will load faster from the internal SSD, but games will do just fine from SD cards as well. When IGN came to us, the games they tried (and captured footage of) were installed on a card. SD. “
The bottom line is that it will be possible to increase the Steam Deck data storage space without fear of excessive-performance drops in-game uploads.