> The kind of site that is rare today but used to be most of the internet, and we're all worse off for the change.

To me, it is not that these sites are rarer today than they once were. In fact, I think they are more of these today. It is just that the internet today is way bigger than it once was, and a lot of crap came with it. In fact, the web page dates back from 2000, and believe it or not, what is now known as enshittification was well on its way, though it was more Flash than Javascript. It was the peak of the dotcom bubble after all. The time such websites were "most of the internet" was more of a 1990s thing.

A site like Ian's Shoelace Site is not representative of its time any more than it is now, in that it was, and still is unusually good.

> Also, because it uses core/standard web technologies exclusively, he has never been required to change it to keep it working or update a bunch of stuff for security reasons.

On the client side, sure. On the server side, there is still maintenance to be done, especially with https where you have to manage certificates and their expiration, even though certbot make it simpler. But arguably, that's his host job and he just has to upload a bunch of html file, so you are right on that point. He still kept his page to modern standards, even though he wasn't required to (HTML 1.0 still works!).

> A site like Ian's Shoelace Site is not representative of its time any more than it is now

It very clearly is, though.