So, in order to bring a response: I solved this by disabling the Intel UHD graphics through devmgmt, and enabling it again. Nothing else. I've now got a Start Menu!
Did a clean install of the public release Windows 11 on my XPS 9510 today. The start menu won't open. Produces a crash for the startmenuexperiencehost.exe process in the Event Viewer - it can't be started. I tried reinstalling Windows 11 to no avail. Tapping the start menu quickly 6-7 times will briefly show the start menu, which will then crash in less than a second. Any ideas where to go from here?
Dell XPS 9510 Windows 11 Start Menu not showing