I am having the same issue - UE 5.4 must be force quit after the program has quit. Sometimes, the crash reporter will need to be force quit, also.
MBP M3 Pro 14" (2023)
36MB RAM
OS 14.4.1
UE 5.4.1
UE project based on blank VP scene
Otherwise, UE is running as well if not faster than on my PC.