I've clung to Aperture since its support was discontinued, and finally cut the ties when I moved my desktop to Catalina. I deleted the Aperture app, since it would no longer function. Recently, in ACDSee, I noticed the Aperture library still appeared. If I looked in Finder, the library icon appeared, but no sub folders, so I assumed it was "gone". But in ACDSee, there were hundreds of images in there, some of them heavily processed TIFF files of several hundred megabytes. I have never used Aperture as a filing system, but, however I was using it, it had built a substantial horde of large image files in its library, most of them duplicated elsewhere in my own filing system. So I started laboriously inspecting each one and determining if it was a duplicate and could be deleted, or was needed ( a few were). In the end I deleted 50 gigabytes from the hard drive - enough to store about 1000 large RAW image files. I don't use Photos, but if I am not mistaken, it creates a library too, as do other popular photo apps (like Lightroom I think, though I do not use it). I have always preferred to use my own filing system, and open images in any of the several apps I use as needed. But if you are doing the same thing, check to see if you don't find numbers of duplicated image files stashed in some app's library.