They would stand in the way of every layoff and changes they don't like, that's their mandate, unions are just another entity fighting for the status quo and another hoop a company needs to jump through.
If the costs for major expenditures were lower people will have more resources to climb the socioeconomic ladder, and we won't need to decrease the dynamism of the labor market and saddle corporations with more obligations to achieve that.
Oh and companies shouldn't pay for employee healthcare, that's a WW2 relic that only benefits health insurers by keeping costs high.