S3 was one of the first offerings coming out of AWS right? It’s pretty legendary and a great concept to begin with. You can tell by how much sense it makes and then trying to wrap your ahead around the web dev world pre-S3.
? The web dev world pre-S3 was pretty much the same, but you stored your files on a regular server (and set up your own redundancy and backup strategy). Not that much different to be honest from an end user's point of view.
At a lot of places there wasn't even a redundancy nor backup strategy, so it really was just as simple as registering with a hosting company and ssh+ftp (or cPanel or something like that for what amounted to the managed solutions of the time).
I agree, things before S3 weren't really that different. LAMP stacks everywhere, and developer skills were very portable between different deployments of these LAMP stacks. Single machines didn't scale as much then, but for most small-medium sites they really didn't need to.