That was one of my original goals as well, but unfortunately there aren't many (any?) sources of downloadable art tagged with metadata. Hence, just the filename in the pop-up menu.
I've thought about creating an open dataset that is free to use/download (everything is in the public domain anyway). The thing is, I have around 250GB of images (all images available in 4k) and I'm put off by the cost of hosting. If I were to just serve 2K images then the set would only be around 20GB.
Any suggestions for how to serve such a big file from a website?
I could just make it available as a dat (https://datproject.org), but it's not exactly a widely used technology yet. Maybe I should just make a torrent? Ideally I would be able to update the dataset in the future.