Approx 20 years plus is vintage (in case anyone is confused).
Ahh, I didn't realize that you are owning the official definition.
I have seen various different definitons applied, e.g. by the organizers of vintage computing festivals. I like the criteria most European vintage computer organizations seem to have gravitated towards: "Older than XX years and
interesting, which typically excludes Windows PCs", or something alsong those lines.
Of course these criteria are not absolute, and Windows machines can be quite interesting, e.g. if they have a unique form factor. And you can probably find some machines/devices which are quite a bit younger than 20 years, and are nevertheless of interest to (some) vintage computing enthusiasts -- either if they were groundbreaking innovations, or quirky dead ends of the technology roadmap.