This is what very polite racism sounds like.
So Im failing to see how it's racist, rather than merely an unpopular view with which you disagree.
And if it's not racist, it's extremely inappropriate for you to label it so. That tactic is meant to silence legitimate disagreement with hyperbole.
> bigotry: intolerance toward those who hold different opinions from oneself
It sounds like the OP is perfectly tolerant of them existing and doing whatever it is they do, but thinks there are cultural factors that make some people more productive or better to work with than others.
This is obviously true -- education, shared language, a certain amount of tolerance from them -- are all things we expect to be cultural factors in employment.
The OPs point is about what cultural factors and values are most important for and best at jobs.
How is that being a bigot?
And since the OP's culture was clearly a white man's culture - a culture that has been relatively slow to accommodate others, in many ways its still a racist, sexist vision - granted one with unusual bluriness at the edges.
White people (in Canada, at least) flock to management consulting, investment banking, law, and medicine and look down on software developers.
You're putting too much emphasis on the race part of the word, and not its meaning of exclusion using factors beyond an individual's control. You are the one being hyperbolic.
Also, culture is something you control: even by your definition, it's not racist. (Though, really, you want a term like 'discriminatory' when talking about all factors, because racism is about race.)
As chrismealy says, swap in 'bigoted' for 'racist' if you want to be pedantic; his point still stands. It's not "extremely inappropriate" at all - the OP still a polite form of excluding people wholesale on factors that they can't control. And no, culture is not something people can "just choose" when you're working at demographic scales.
And 'white culture' does not exist. It's not a thing unto itself. Spanish vs Irish vs Russian vs Slovak are all significantly different. White greeks have more in common with the brown people of the eastern medditeranean than they do with the redheads in the celtic lands. You can't just say "MY culture" and take everything that Europeans and North Americans have done.
Edit: I do think the heritage thing was unnecessary, unless used in a context of cultural differences and the therewith coming need for integration.
I don't think it's fair or useful to demand each culture to build their own technology from scratch, I think that's crap. I do think it's fair to ask immigrants to adapt to the local culture to the point of tolerating it.