PS/2 keyboards are early 1990's.
PS/2 keyboards are early 1990's.
I'm also quite certain there were also no USB flash drives, SD card support, Wifi networking and e-ink displays in the early 1990s. It's not a replica in any way, it does not claim to be that. Just a cool compute device!
"I built an XT 'clone' [that doesn't even target the same CPU as an XT]"
And until a couple of days ago, I never heard anyone mention an "XT clone" as being an emulated 80186 on an ESP32 with almost none of the IO or expansion capabilities of an XT.
That appears to be a new usement of the term; an invention, if you will, or a perversion if you won't.
(I can emulate an XT with my pocket supercomputer. It's fun to play with that kind of thing sometimes. But to call it a "clone" is going too far.)