I think what he's suggesting is that minorities find our community unwelcoming, and by unwelcoming they're probably referring to the racism and sexism that's rampant in the tech community. Unlike you, they're not worried about being turned away from a job for not being a hipster, they're worried about being turned away from a job for being black or a woman. Or, worse, they're worried about the abuse and disrespect they will undoubtedly get while working in tech.
Cmdkeen explicitly refers to dress codes, benefits packages and socialization patterns, not abuse, disrespect and racism.
People constantly talk about racism and sexism being "rampant", but evidence of this would be helpful. Citing statistical disparities is insufficient since, as cmdkeen notes, this could also be caused by "tech minorities" disliking the culture of tech rather than techies disliking them.
In some (very loose) sense, those two things are the same thing. It's not that these people say to themselves "man, I hate how I can't wear X shirt to work, better quit" but rather "the culture here (dress code, socialization patterns, etc) seems to default to white, and people view me as an outsider." I think that that's probably much more common than explicit disrespect.
They aren't the same thing. One is something that is done to you, the other is something you choose to do to yourself (or not, if you find it more useful).
My company is about 95% one race (not mine) and there is precisely 2 people here of my race (since last week) and 4 of my nationality. I simply choose not to care, and define my work tribe as "folks who care about uptime and good stats" rather than "folks who are genetically similar".