You hear a heck of a lot more about it on HN than happens in reality.
Maybe I don't hang out with the trust fund crowd enough but I don't know ANYONE who's taken a "gap year" where they weren't doing something for ~40hr/wk in order to make a buck. I know a few people who didn't jump right into career stuff after college but even they did low pay large applicant pool type jobs at least tangentially related to their careers (e.g. working as basically unskilled labor on tourist fishing charters in Miami before getting a real entry level job on a container ship). Heck, even the people who took a year off before college were doing stuff tangentially related to their career/skillset in that time (e.g. working for geek squad prior to going to school for CE). I know a couple people who went from full time to part time or to less demanding jobs in their field prior to retirement. I know a couple people who did jobs not related to their vocational training for less than a year after they got out of the military but that was more of a stopgap to keep a roof over their head. I don't know anyone who's gone from full time to part time or less unless it's part of a career transition or approach to retirement. I'm sure there's someone somewhere who's managed to pay their rent by waiting tables and stripping for a grand total of 15hr/wk and spent the rest of the time doing art or writing a book or something. I'm sure there's someone who's banked a ton of money and taken a year off in the middle of their career. I don't know anyone who's pulled something like that off.