@gmorin I may have it behaving better now, but we'll see how it goes over the coming days. Unfortunately, I can't remember if this is everything I did. However, the main thing I absolutely know is I did was Device > Erase All Contents and Settings on the 18.4 Simulator.
When the Simulator came back up, I briefly saw it perform what appeared to be an update (?) of some sort. I'm sorry I didn't pay closer attention; I was doing that in the background while working on something else and didn't expect to see anything out of the ordinary.
But I'm quite certain an Xcode reinstall would not fix this, because I had done a full wipe of the hard drive with full OS reinstall (with applications like Xcode) just 24 hours prior.
(the OS reinstall was because of a macOS failed update that "bricked" my system, while we're on the topic of bad updates)
