I'm of the opinion that the nostalgia for personal webpages is completely overrated. HTML/CSS as a whole is a poor medium for visual design, and was never meant to really serve more than CERN's internal technical encyclopedia. We've spent the last three decades forcing it to be the everything format, but it's really obvious once you start play with formatting that everything beyond a linked encyclopedia is a complete kludge. Static HTML is at least easy enough to write but your website is completely autistic (one sided, non-verbal) unless you rely on some centralized third party format (Email, D*scord, etc.) to contact other people. Dynamic HTML is a huge pain in the ass to write yourself; even just setting up a VPS and managing a bunch of CGI scripts, though not hard for a technically minded linux autist, is way out of the league of anyone who isn't a massive nerd.

You also have the problem of most people who host webpages being boring and having nothing to say, at least not with some kind of "architecture" around them to plug themselves into. So you're left with things like Neocities being mostly comprised of awkward graphic design experiments and pointless blogs.
I can't exclusively blame HTML for reality failing to live up to the cool Japanese turn-of-the-millenium "teenagers in underground dance clubs creating doomsday cults" thing you see in Lain or TSC, but maybe you get what I mean.

In spite of that I still have a collection of personal websites that manage to be cool regardless, so I can at least dump a bunch on you anyways in exchange for reading my textwall.

I'm in no way a Lolita guy or even a Fashion guy but my favorite is this Lolita Fashion themed homepage:
https://ita.toys/
This feels more like an extension of the author's fashion sense than a webpage, it's so fucking cool. Also, in case my earlier tirade against HTML didn't make sense, take anything from the scans section and look at how pretty and cool the layout and visual design on any of those magazines is. The bleeding edge of web design in 2026 is barely meeting 90's-00's print magazines halfway.

https://campanella999.de/
Here's one of my friend's personal webpages, with some of his own art, some film, anime and game fanpages, and translations, very cool guy.

https://handprint.com/HP/WCL/water.html
A watercolor painter's webpage, a ton of information of paint, pigments, color theory, watercolor history, etc. that's hard to come across anywhere else on the net. Also a really well designed "minimalist" website that actually looks nice.

https://jaharrison.me.uk/index.html
I found this one while looking for information on the math behind bell acoustics, this kind of design is basically what HTML was made for.

https://pigmhall.net/menu.html
A really cute loli artist's electronic music and music video CDs.

http://number2-takuji.com/
A lot of eromanga artists have cute personal pages like this. I'm too dekinai to really browse them properly, and a lot of them are on now defunct geocities clones so you can only dig 'em up on Archive. There's a lot more cool stuff on the Japanese web in general.

I probably have more on some other hard drives. OP, are you looking for personal websites specifically, or just cool web design in general?