I have been asking about this since March 2019, but it is still not mentioned. Of course, this would mean folders and subfolders would be visible …For now, LR and ACDSee allow it.
Previous topic about this : Select multiple folders
Do I understand right that projects in PhotoLab are not an option for you? Or do you just see the ability to select multiple folders to work in as a better approach?
Yes, absolutely ; if you look at he topic I inserted a link to, multiple folders selection is part of my workflow.
Projects in PL need to be filled first. But if I’d fill project with all pictures just to see them all and browse through … well, PL is not the fastest viewer. Without a catalog holding size-reduced JPGs, scrolling through a couple of 1000 images is is simply too slow.
Meaning: even if PL could show multiple folders, you’d probably be disappointed about the culling speed.