Collective bargaining means bargaining at the point of a gun. It has no place in a free society unless the membership in unions is voluntary, and the bargaining table has fair participation of both sides. Freedom of assembly becomes a sham when union membership is coerce and union representation is a government-enforced monopoly.
One example of an unfair bargaining table is when public sector employees are represented on one side of the table, and the other side has their representatives. This situation is what typically occurs, with no taxpayer representation at all.
The National Labor Relations Board, the NLRB, formed under President FDR gives totalitarian control to unelected officials. Any such system cannot be fair.
There needs to be checks and balances in a political system. We need to eliminate all political control systems where checks and balances have been removed. The NLRB should be abolished, and the National Labor Relations Act of 1935 which established it should be repealed.