That’s not the same thing. Trademarks become generalised terms in the public’s mind, not legally. Two people in conversation might refer to a non-Xerox photocopier as a Xerox, but a non-Xerox photocopier company can’t just advertise their products as being Xerox.

Additionally, from the wikipedia page you linked (emphasis mine):

> A trademark thus popularized is at risk of being challenged or revoked, unless the trademark owner works sufficiently to correct and prevent such broad use.

Which, again, goes directly counter to the idea of a public domain trademark.

But then it’s not public domain (which was the argument I was replying to). Public domain means everyone can do it without permission, while applying for a certification still requires a governing body which has the ultimate power.

> Things like "Organic" already do that a bit

That’s a classification, not a trademark.