Because that's now employees behave, now employers won't offer anything else - but without offering anything else, employee attitudes aren't going to change.
I think strong unions are the only way forward
In my lived experience, unions permanently cement the anti-employer (and often anti-customer) attitude present in some employees. Once in place, they don't produce a massive change of heart where employees are willing to rise above and beyond the exact terms of their collective bargaining agreements, but instead result in a rejection of the traditional work ethic and the embrace of minimal output and often malicious compliance across the board.
It's one reason many of us have had such bad experience working with unions in the past. The customer suffers along with the employer, and worse the customer often pays a higher price for this privilege.
I think a lot of people in tech are realizing how helpful unions could be right now.