Vanishing iOS Simulator and empty OS selector

I've been using Xcode Version 15.2 iOS simulators on Ventura 13.6.6 without problems until this week.

Now, a running simulator window will simply disappear at random times.

If I go to File > Open Simulator to respawn it, there are no options available:

So then I go into Xcode and try to create a new simulator, but it thinks no iOS Runtimes are installed:

However, when I choose Download more simulator runtimes, they are clearly still there:

A reboot seems to correct this issue, but obviously it is impractical to disrupt my workflow by rebooting throughout the day.

Activity Monitor does not indicate any resource starvation issues, and I've found no other correlating events that might point to a cause. This is truly baffling.

Does anyone have some insight into why this may be happening and/or how to avoid it?