That's what you took from that? I provided a big list for various contexts and that's what you focus on? Anyway:
"A dude cut in front of me in line" did you happen to note what you pictured when you thought of a dude cutting in front of you? Assuming you don't have aphantasia.
"A person cut in front of me in line" both acceptable sentences in English.
A dude called me, a person called me. I met a dude the other day, I met a person the other day. I'd rather be in the forest with a bear than a person, I'd rather be in the forest with a bear than a dude.
Let's do plurals: 3 people walked into a bar, 3 dudes walked into a bar (they said 'ouch').
If you think "person" is weird ommit it. It's a distinction without difference as it's lack doesn't change my point in any way, shape, or form. This is what's called pettifogging, when even if you're right it doesn't change a thing.