Importing another project into Premiere doesn't work on the first try

Premiere 24.0.3 (Build 2) as well as previous versions of 24 and 23.

Mac OS Sonoma 14.3.1 and previous versions

M1 Macbook Pro  2021

When working in an existing project, if you try to import a different Premiere project of the exact same version of Premiere, the import window will either never load or will take longer than 15 minutes to load (I've never waited longer than 15 minutes to find out if it ever loads.)

With a project file open, select File > Import, navigate to a different project file than the one you currently have open and click "Import". A window "Import Premiere Pro Sequence" opens and says it is loading the selected project. This window should load the contents of the project you are importing from but only shows a blank screen that says "Loading [project name]" (see screenshot).

This blank loading screen persists for at least 15 minutes, but likely longer. For all practical purposes the project content never loads and there is no progress bar to indicate any loading is taking place. The only current workaround is to cancel the import and retry a second or third time which eventually resolves the issue.