In Flickr's case it's because they were owned by Yahoo and basically mothballed for years because it wasn't part of Yahoo's core business.
After languishing without any changes for several years, they got bought by SmugMug a few years ago. SmugMug is a better steward than Yahoo was, but it's hard to make significant changes to a product that's essentially been in maintenance mode for a decade+ without access to the original programmers who actually knew how things worked.
In Flickr's case it's because they were owned by Yahoo and basically mothballed for years because it wasn't part of Yahoo's core business.
After languishing without any changes for several years, they got bought by SmugMug a few years ago. SmugMug is a better steward than Yahoo was, but it's hard to make significant changes to a product that's essentially been in maintenance mode for a decade+ without access to the original programmers who actually knew how things worked.