So you never emerged yourself into the culture? You’re just spilling hatred and prejudice.
I have spent a lot of time on the mainland, just not in Mexico City. I found I was more comfortable in the small villages. My rule was, if a commercial airline few there, I did not go there. Mexico is much like the USA, the bigger the city, the bigger the problems.
And no, it was not about American money. They are a kind generous people. I have been far out into the country driving on back dirt roads with no signs for direction. Stop at a small farm house to ask directions to the petroglyph I was trying to find. I was immediately invited into the home and offered a beer. When he opened the refrigerator, all he had in there was one beer, and he was offering it to me. I told him I was on medication, and could not drink it.
If a Mexican stopped at your house to ask directions, would you even think about offering him a glass of water???