Heads up: I deleted all Safari data, it didn't work. I reset the device settings, it didn't work. I erased all settings, it didn't work. Only after I restored the device back to visionOS 2 with my colleague's developer strap are 3D cams working again, as is the keyboard and chat in Stripchat.
So yes, it is an issue with visionOS 26. I unfortunately need to revert back to 26 again for work, but I advise you to have your team look into the fix, as the public release is only a few weeks away.