Head of Diablo at Blizzard, Rod Fergusson, is hopeful that as the Switch 2 is launched, they can figure out the live service component and Diablo 4 can make its way to the handheld. Diablo 3 and Diablo 2 Resurrected will be playable on the Switch 2 thanks to backward compatibility.https://www.notebookcheck.net/Diablo-4-could-easily-come-to-Switch-2-but-live-service-on-the-platform-has-been-challenging-says-Diablo-head.1003941.0.html
Or they could just drop the live service BS...