The 737 is noticeably louder than other planes on the ground and in the passenger cabin and especially for the pilot. 787/A350 and the A220 have a higher cabin pressure and better air quality that helps you feel better. It could be that most of my wide body experience was going over the Atlantic on 747s in the 1990s and a few times circa 2012 flying 767s on the JFK-LAX route which felt luxurious. As I see it, I’d rather fly coach on a better plane than “first” on a worse plane. (e.g. first on a 737 is like business on a widebody, in an A380 first-class is crazy over the top) 737 first still has your ears ringing, under-oxygenated, feeling cramped inside a small cylinder, etc. Luggage bins are nicer on a big plane too.