No one buys books, cd's, dvd's, blurays, magazines, comics, games, and many other things that were bought a lot 10-30 years ago. These days everything is online and (usually) subscription based. Looking at myself, the only things I buy regularly, is food ;)
Surely CDs have become Spotify, tidal. Blu rays have become Netflix, Disney, etc. magazines have become websites, etc. The content is still there just the medium has changed. Has the same been true for books though? eBooks do exist of course, but did they replace the publishing industry that existed 50 or a hundred years ago?
People have a limited amount of time for entertainment and have a lot more choice between Netflix, YouTube, Books and thousands of other things than they did back then.