Have manners changed completely in America that makes them unlike what you see in Europe?
People don’t introduce themselves on social media. They want to get straight to why they are using social media (often just sex) and they don’t want to actually engage with you. They want to be anonymous and be what they want to be.
It reminds me of all the noise about Meghan Markle who just wants what she wants and not to give anything to anyone else. Sad, and pathetic.