How can Flickr be used for free with unlimited photos?

I have an account with Flickr and I once had uploaded over 200 photos, so I only saw tha most recent 200 of them because I don’t pay for a professional account.
However, the photo pages were still accessible, so the older photos were kept on Flickr but they just didn’t show up anymore under my photos, I had to know the exact URL to access each photograph.
Technically seen, by using a “library” for photos on could just add them with their link and always have access to them even without paying! Does such a library app exist?