The "everyone else" is not meant to be read literally.

Many people are well-paid, or even overpaid. CEOs, for instance.

It's just that most people, in most common professions, are underpaid.

It only makes sense to talk about a blanket statement like that being a "contradiction" when someone is attempting to speak in the language of formal logic or detailed argument, not colloquial speech.

That's fine, then the response I was looking for is simply "I didn't mean literally everyone else, I just meant simply 'most people, in most common professions, are underpaid'". That's a perfectly valid point of view.

Then I would have replied that, despite perhaps being true, I don't how it's relevant to the question of whether it's fair to pay train drivers and pilots the same.

You don’t get it because it doesn’t make sense. People’s understanding of money is horrible.