Still doesn't make it look good. If thats an issue they could always have an optional setting to enable colorblind mode.
And if colorblind people aren't inconvenienced (and don't have to navigate to a menu to de-inconvenience themself) then that's enough of a reason for me.
Side note: I'm surprised there isn't a specific header browsers could send for something like colorblindness. That would allow sites to react to that header and serve up a different stylesheet.
Accept: text/css; color-blind=trichromatic
Of course no server would recognize this today, since afaik the CSS media type doesn't define any parameters other than perhaps `charset`, but the mechanism is there at least. Also any self respecting web server would just ignore the parameter so it shouldn't break anything, just cost a few more bytes of bandwidth I guess. No need to invent a new header I don't think.