I don't think this is really unique to Web 1.0; certainly something that still works from the Web 1.0 days seems "impressive" just because of the passage of time, but there's probably some element of survivorship bias there. You mention ColdFusion as an example, but this guy's site is made using FrontPage. He didn't know in 2001 that he'd still be able to run FrontPage in 2020. He made a bet, and it paid off. Other people made similar bets, on other technologies, and unfortunately got it wrong.
My personal website uses Jekyll, and while there's always the possibility it would become abandoned and stop working (I've definitely found someupgrades to be a pain, and ruby tooling in general doesn't help either), I'll always have the simple, readable markdown files the site is based on. While this wouldn't be an option for a non-technical website author, if I really had to, I'm sure I could write a simple markdown->html renderer over a weekend (or a converter to transform it into the future format-du-jour).
My personal website uses Jekyll, and while there's always the possibility it would become abandoned and stop working (I've definitely found someupgrades to be a pain, and ruby tooling in general doesn't help either), I'll always have the simple, readable markdown files the site is based on. While this wouldn't be an option for a non-technical website author, if I really had to, I'm sure I could write a simple markdown->html renderer over a weekend (or a converter to transform it into the future format-du-jour).