When I launched minecraft Java on my steamdeck I went to the audio settings. I changed the default device and it made Minecraft completely unresponsive. I tried redownloading the launcher. That didn’t work. What helped fixed the issue was going back into Minecraft. Tapping on settings once. Tapping on audio once then tapping on device once to change back to default. It was so unresponsive I had to tap once and wait till I got to settings. After it changed minecraft was fully responsive again.