I had to go into application support to solve a problem (now fixed) and noticed that I have a ridiculous number of application support files for old verisions of Illustrator and Photoshop. Some of the subfolders in these folders have nothing in them, and some have a lot. Can I safely delete these files? All my Adobe programs are a bit slow and wonky in Catalina and I'm trying to avoid erasing and reinstalling Catalina. I have attached a screen shot.
Unless there are plugins or extensions being accessed by the new versions from the old folders - this actually has NO bearing on the performance of your current Adobe product.
That being said, you should be able to safely delete all of the previous versions. The only exception likely being if you're having your new version access any plugins or extensions that may have been installed in there. Look through them. If there're no fonts/plugins/extensions/saved brushes/presets/etc in them, it should be safe to discard. Please always make sure to have a great backup - AND to NOT throw out any part of the current Adobe Apps.