I think its because through experience people have figured out a lot of unspoken things about what its really like being an employee. They have figured out that its much more about connections and office politics than hard work. They have figured out that there is really no job security, and they could be one layoff wave away from unemployment. They have figured out that its much more about face time and spending lon…
A little bit too cynical for my taste. You make it sound as if companies serve no purpose other than extracting value from the employee to the company. Your work value inside the company is higher than the value of the work per se; the order that the firm institutes has a value for society, minimizing information, decision and transaction costs. That is why firms exist, and not only markets; a gig economy in which everyone is free to sell their work is worse. You could even argue that the power relations that the firm embodies for you end up also appearing in a market, without the securities of a job relationship (see Uber drivers and the like).
See https://en.m.wikipedia.org/wiki/Theory_of_the_firm
Also, job security is not perfect, but it sure does exist.