So what? 500 years later, a typo could be part of the English language taught in school. It doesn't mean that every single typo has to be accepted from day one as valid. Otherwise the mere concept of typo, or even the concept of English language itself, stops meaning anything.

I don't get the urge many English speakers have to justify any deviation (i.e. any typo) as valid and indisputable. There's grammar nazis, but there's also illiterate people :)