I think there's some truth to that, but I don't think that's the only factor in everything the article described, and it's not specific to blue collar work.
There's a lot of actual prejudices (not just banter) among, say, "educated" tech industry workers, too.
Including sexism, racism, ageism, and classism.
Most people will at least superficially hide it in modern workplaces, but it's still there, and having effects.
You've probably seen evidence of this places you've worked, and you can also see it often in pseudonymous HN comments.
There's a lot of actual prejudices (not just banter) among, say, "educated" tech industry workers, too.
Including sexism, racism, ageism, and classism.
Most people will at least superficially hide it in modern workplaces, but it's still there, and having effects.
You've probably seen evidence of this places you've worked, and you can also see it often in pseudonymous HN comments.