I'm originally not from a rich country. Before I became a Swedish citizen I never had a bad experience traveling back into Schengen, border agents were always

I'm originally not from a rich country. Before I became a Swedish citizen I never had a bad experience traveling back into Schengen, border agents were always cordial even on the instances where they were stern and serious. Even had nice interactions sometimes, at Schiphol with Dutch agents once they were quite funny, and light-hearted. Every single time I traveled into the USA I experienced CBP agents being rude and suspicious, treating people like cattle on immigration lines, being talked down when being questioned, etc. The experience applying for my B1/B2 was also really annoying, not a great one being interviewed and grilled by a consul. It's definitely different to go through USA's borders than most other places I traveled to.