Frankfurt is a great city because there's nothing to do

True! Out of the big cities in Germany, Frankfurt is perhaps the most vile. Huge financial skyscrapers (and homeless drug addicts on the streets below), luxury shops, more skyscrapers, residential areas that look run down and mainly inhabited by ethnic and national minorities.

I haven't been to the United States (and don't want to) but it's exactly how I imagine an American city, except with a better public transportation system.

I'd walk with my hands in my pockets at the station too, it's common sense in station areas anywhere you go to tbh.

"$30 Euro" is not enough for Frankfurt-München lol, neither by high speed rail, nor regional train nor bus. You can get the Bayernticket for 27€ for slow trains in Bavaria I suppose, but it's 6h + to München.