There are so many articles shared here on developer depression, burn out and so on. Maybe you should try speaking with some actual janitors, some of them do quite ok. Maybe some are actually happy, because now they have a job to support their family and are not on the run anymore. Or they did not bind their happines to their bank account and find meaning elsewhere. Or maybe they rather do cleaning, than feeling proud to know how to game SEO and flood the world with shitty adds or alike.
They can’t afford families because they can barely afford to rent a room in a basement an hour from the office. Sometimes they share a bedroom so they can send some money back to a developing country I guess?
If they were born early enough to be home owners then they probably increase their net worth by more than me every year and it makes me feel like shit for losing the real estate lottery