Promise of what?
I think the major change with millennials and gen z is that we see through the dogmatism that is corporate culture. Even if the promise was that of the "American dream" 50 years ago it's quite clearly not worth it to sacrifice your youth and 1/3 of your life (another third being sleep) to afford to sit around in a house and squeeze in stagnant social obligations for the rest of your life.
Life is what you make of it, and familial loyalty to a company that doesn't care about me just doesn't cut it.
In my experience, small businesses can be even worse, because they're run by the kind of middle management that everybody hates in a big company. Except now they're the boss and have final say over everything that happens in the company.
My brother works for a small business. They got him in the door by being his buddy, just fun-loving fellow millennials who love to have a great time at work while having plenty of opportunities to move up within the company!
...he hasn't gotten a raise in three years, and has had myriad issues unfairly pinned on him (legitimately) so he can't move up in the ranks.
They're just young boomers doing the same boomer shit, but they're a little younger and cooler, bro!
Yep, worked for a small business as a teen. My experience was that the boss was decent at giving us raises every year, but got pissed when people gave us tips, never had enough people on hand to account for kids going on vacation or getting sick, and, as my buddy would say, "he's the first person to tell you that there's more than one way to skin a cat - but his way is the right way." Dude couldn't understand why kids on their summer vacation wouldn't want to work 45 hours a week.