how can I uninstall older versions of photoshop if I've already upgraded to Catalina? Will Adobe offer new uninstallers or do I have to uninstall Catalina go back to Mohave, unisinstall PS and then reinstall Catalina!!
You should just be able to uninstall Photoshop without dealing with the OS. Moreover, you can install several different versions at the same time. When you're in Creative Cloud, just click the ... > Other Versions.