This is...not true? Or at least I can find no basis for your claims.
UK Copyright for books and sculpture predated the invention of photography and existed in a completely recognizable form ("a copyright term of 14 years, with a provision for renewal for a similar term, during which only the author and the printers to whom they chose to license their works could publish the author's creations.[4] Following this, the work's copyright would expire, with the material falling into the public domain"[1]).
Paintings and photographs gained copyright protection at the same time, in the 1862 Fine Arts Copyright Act, seemingly because it seemed natural to extend the haphazardly covered fine arts more completely.
They said you couldn't become a good photographer if you didn't learn it with the limitation of film that forced you to make each shot count. Photoshopping a picture made it "not a real photo" and was banned from online communities and irl events, drawing in photoshop was not considered art. I find it very ironic that digital artists are repeating the exact same argument as the one used against their art