This is where I quote a Narina meme and say "Don't quote the old magic to me..."
You're engaging in survivorship bias. One of my first 'social' media/forum accounts accounts was lost when the admin of the site dropped the user table from a database, and had to go back to everyone online and ask for people to mail in about their accounts. I never bothered to set it back up.
Piles of other smaller sites disappeared for similar reasons. If you completely ignore all that, then yea the old internet was fine. Oh, and that these days hackers are highly motivated to encrypt all your crap for bitcoin.
Typically big sites don't disappear because they depend on separation of duties between different teams doing their responsibilities. For example, knowing how backups work and making sure they are working every day.