I have the same issue with the Search Bar not working after update to Windows 11 23H2.
I have tried all the fixes and none of them have worked.
The thing I noticed is that there is no Windows Search running in the Task Manager Processes.
The only way the Search Bar will work is in Safe mode.
Any more new ideas ? This surely is a common issue the Windows 11 23H2 update as there are tons of user's with the same issue.