>Because more money is what most candidates prioritize when job hopping, because when buying a house they can pay it with that money but can't pay it with more time off.
Although you could argue that's already the case in a lot of Europe vs. parts of the US. Of course, it's an imperfect comparison because of the barriers to moving countries or even acquiring a remote job in a different country.
And money is money, it's a known quantity. Time is more ephemeral and for many "knowledge jobs" people work off the clock anyway; so having every Friday off may sound great but you may be (correctly) afraid it's going to turn into a half-day's work anyway.
And there are things you can do to turn money into time, it's possible but not as easy to go the other way around when you're salaried.
Conversion is difficult without e.g. working at at a company that lets you take a week or two or two of leave a year (or just looking the other way). You can have a side business but that's harder to turn into something that's actually financially competitive with a professional-level salary and isn't ethically questionable.
Although you could argue that's already the case in a lot of Europe vs. parts of the US. Of course, it's an imperfect comparison because of the barriers to moving countries or even acquiring a remote job in a different country.