You ssem to be the only one with this definition, hence the only one redefining it."Vintage" is entirely age. It has absolutely nothing to do with quality or craftsmanship. Anyone claiming otherwise is attempting to redefine the term.
''Vintage is quality and craftsmanship''..... pah-leeeeez!!
The 'original' term was linked to wine production, going back several hundreds of years. But like many words in all evolving languages, vintage took on other meanings. Vintage as applied to wine has no bearing on vintage as applied to mass produced guitars.
Vintage means old AND of superior quality, it being for wine, instruments or anything else. A crappy chinese or russian bass from the 60s isn't vintage. It has no superior quality and little value.
Oxford Dictionary:
vintage
Pronunciation: /ˈvɪntɪdʒ/
adjective
1. relating to or denoting wine of high quality:
vintage claret
2. denoting something from the past of high quality, especially something representing the best of its kind:
a vintage Sherlock Holmes adventure