Books in the 17th and 18th century often didnt get bound by the publisher. They were done by independent binders for _custom_ orders. You’d see whole libraries with the owners binding/cover standards rather than per book.
Books in that time were _luxury_ goods. Most people could not afford them. One of the ways that was changed was to introduce cheap, mass produced bindings that were lower quality than the bespoke artisianal bindings done by specialist craftsmen.
You can still get custom bindings done. There exists whole niches on the internet of crafters that will take a production run book and strip its binding and make you extremely high quality and custom bindings and covers.
Books in that time were _luxury_ goods. Most people could not afford them. One of the ways that was changed was to introduce cheap, mass produced bindings that were lower quality than the bespoke artisianal bindings done by specialist craftsmen.
You can still get custom bindings done. There exists whole niches on the internet of crafters that will take a production run book and strip its binding and make you extremely high quality and custom bindings and covers.