I just tried deactivating my caching and security plugins before exporting. No change in behavior. I looked at the browser’s console (F12) and there are no errors.
I added “wp-admin” to the end of the URL hoping I could log into my control panel, and I got this screen:
Note that when I first launch the site, it doesn’t complain about SSL, and I was able to get MacOS to trust the local certificate by going into the Keychains app.