>If IPO makes CEO much, much richer but generally also makes company and workers better off (but to smaller degree), does IPO make workers more undercompensated?

Yes, obviously. The bulk of work of the company is done by the workers. That is to say, most of the value is generated by the labor of the workers. If a commensurate share of the profit is not returned to the employees, they’ve clearly been undercompensated.