Earlier quoted context omitted.
That's an interesting point, however I disagree it's tolerance of one group that makes someone intolerant of another group. In other words, I don't think being tolerant of black people means I must be intolerant of white people. Karl Popper wrote about this idea called the paradox of tolerance [0] asking if you should be tolerant of intolerance. [0]: https://en.wikipedia.org/wiki/Paradox_of_tolerance
Intolerance of anti-black people makes you intolerant,not tolerance of black people. That intolerance would be fine(I certainly don't tolerate anti-black people in my personal life) but I would want to make every effort to be professional and respectful towards a skinhead at work.
I do not intend to have a Philosophy 101-level debate here, but would like to say that some things are not morally ambiguous. It is fine and good to be disrespectful towards skinheads at work, on the bus, or anywhere else. It is not fine or good to be respectful towards skinheads. Someone who wishes violence against a class of people based on their race does not have a place in a well-functioning society for these beliefs to be openly tolerated and accepted.