I did the Philadelphia to Boston trip by plane once (I live in Central New Jersey), only because I had a business meeting at 12 PM. The Acela doesn’t stop in Trenton, so while I preferred the train waking up at 5am didn’t appeal to me. If I go again I’ll prioritize the train. City pairs in US that should have high speed rail: youtu.be/wE5G1kTndI4