GP's discussion was a mega acquisition; there's a lot more ability to setup retention grants for each individual on those.
Even on a mega ipo, there's some opportunity to make stock grants before or after the event.
In both cases, team size matters. If there's a budget for retention or $1B and founders get 90%, that leaves $100M for regular employees; if you've got thousands of people to retain, the payouts won't be large. With a team of 100, the payouts will be nice.
I'm just not sure why you think junior level employee #20 deserves more than what he agreed to when he got hired. Clearly he was making a full salary, probably with benefits, that compensated him for his work. He took no risk whatsoever.
I'm sure if junior level employee #20 said, "I'll work for half price if you include a bit more equity" there would be a lot of companies that would accept. However clearly he didn't want to take that risk at the time, so why should he get the reward?
Even on a mega ipo, there's some opportunity to make stock grants before or after the event.
In both cases, team size matters. If there's a budget for retention or $1B and founders get 90%, that leaves $100M for regular employees; if you've got thousands of people to retain, the payouts won't be large. With a team of 100, the payouts will be nice.