who in their right mind would shell out 100k + relocation and not require some level of commitment?

People who are going to pay them enough money that they stay specifically because of the money?

The whole reason most people stay at jobs? (Theoretically)

That's the whole point. It distorts market forces when companies are allowed to just trap people.

A company paying half a million annually to ensure this employee is retained. It's not meant for joe sixpack making $100k/yr as an underpaid consultant.

If the talent is that good and you are paying above market you would. Not much different than a signing bonus

They had no problem offering 7-figure salaries to PhDs with research experience in AI a few years ago. Those are the exceptional workers the program was supposed to be bringing in the first place, not dime-a-dozen JS vibe coders.