Yes, Mac. I’ve never had them come back when closed. I wonder if there is an issue with the .json file that remembers them.
Edit: I should have been clearer. The relevant file on a Mac is
~/Library/Application Support/SketchUp 2020/SketchUp/PrivatePreferences.json
First quit SketchUp. Then rename that file and restart SketchUp. SketchUp will rebuild the file as it starts. Your personal settings will have been forgotten, reset to defaults. But if there was a problem with the json file, that should have repaired it, letting SketchUp remember settings in the future.