Forspoken works on the Steam Deck, albeit with longer load times than PC or PS5. I think the DirectStorage feature is simply ignored if not supported by the system, so I wouldn't worry too much.
As one of the few people who actually thoroughly enjoyed Forspoken and has 100+ hours in it, going from that game to D4 felt rather jarring. Still does. As the game from a much bigger company, with a much larger budget and development time, I really expected it to have instant fast travel at release. Especially since they kept using the huge OW as a selling point...
ive yet to try it on pc, but my ps5 games load so amazingly fast, i cant believe it. Fast travel in Spider-Man is literally just a second fade to black.
also, blizzard... where is my ray traced lightning and shadows?