No he says specifically that this doesn't apply to ESL or dyslexics. As a writer...

excuse-me on July 20, 2012 | parent | context | favorite | on: I Won't Hire People Who Use Poor Grammar

No he says specifically that this doesn't apply to ESL or dyslexics.

As a writer he is objecting to hiring people who don't care enough about writing to use grammar correctly and he believes that this also strongly correlates with being a good programmer.