I'm not sure if you're serious about the internet dying, it is basic infrastructure that improves efficiency for everyone from governments and corporations to individuals, it is not limited to being a source of information and entertainment, or a platform to express your opinion.
Calling it an infrastructure might not be accurate, the internet at its core is a global network of interconnected machines, the widespread connectivity is what makes it the internet, such a concept will still exist even if hardware advances.
Regarding purging online stuff, some people might find sentimental value in reviewing what they used to watch/listen to many years later. If you have issues with storage space, just store a text list of music you've heard, links to videos/articles you've watched/read, names of movies/shows/books/games you've watched/read/played, and add a date for additional context for future you. As for images, do not delete any of your personal photos but also keep them safe, memes can be deleted because popular ones are readily available and the rest don't matter. Non-personal photos mostly don't matter unless you have some use for them.
Digital "hoarding", for lack of a better term, is not a new problem, but is much easier to achieve than physical hoarding due to cheaper storage in terms of physical space. People used to and still do collect physical tapes/disks/newspapers/posters/books.