I, too, am not the least bit nostalgic about the 486, Pentium, Pentium Pro, Pentium II, and later machines that I owned.
I think for me it's that they are too much the direct ancestors of current machines. There's basically zero software from that era nor any modern software written for these machines that really cares all that much about bus timings or cycle counting. It runs just as well or even better on modern machines in an emulator.
I'm not a big gamer, but even if I play later-1990s era EGA/VGA games on a modern PC, it feels basically normal to me.
I am nostalgic about machines older than that, particularly the mid-to-late 1980s machines that I grew up with. I now have decades of experience writing software. Even though I don't do much with hardware in my day job, I do know my way around hardware interfaces. I can read schematics and chip data sheets and know how to make it work. And what's nice about these machines is that many of them came with schematics and hardware register descriptions. Even if the paper is lost to time, someone has scanned them in and put them on the internet.
So I like to tinker with them. I like making them do things I wished I could do 35-40 years ago. I especially like when I can do it with pure software. Once such example is a DOS driver I wrote to make Tandy ROM drives accessible to (newer) non-Tandy DOS versions. https://github.com/dfelliott/tandy1000-romdrive
I had a 1000 TL I think I got probably late 1988 or early 1989. Back then I had a 40 MB hard card and it had to be partitioned because of DOS's 32 MB limit. When I upgraded to DOS 5 in 1991, literally going to the store the day it came out, I was dismayed to find I could no longer run Deskmate which was one of the main reasons to own a Tandy.
A few years ago I bought another one (my old one sadly bit the dust in a natural disaster) and went to work on fixing the problem. The journey was fun, and so was the end result. I finally got what I wanted, a machine running Deskmate and other software on DOS 5.
Coupled with my "sci-fi" Gotek I now have a machine that does a really good job of behaving like a machine of that era, because it is a machine of that era, running my old games with Tandy graphics and sound exactly how they ran back then. And I have real nostalgia for these games. There's something neat about what could be done with hardware of that era.
Emulation is just not quite the same. There's something about the CGA rasters on the tube that just feels right.
Plus, even though the machine bit the dust, I still have my old floppies, which I've started reading in with a Greaseweazle.
The Gotek doesn't really detract from the experience, it just takes away the drudgery of dealing with actual floppies and avoids wearing down what little is left of them.