To be blunt, most of my observations of traditional unions have given me the impression that they prevent the hardest workers from advancing and protect mediocr

To be blunt, most of my observations of traditional unions have given me the impression that they prevent the hardest workers from advancing and protect mediocre workers who do the bare minimum. The incentives appear to create a negative work environment for those who do want to excel, even in traditional union careers such as teaching and nursing. I agree with you that the trend of asking Leetcode (or any rote-learning) style problems hurts candidates. I have no moral problem with software engineers bargaining collectively to reverse a trend that is harmful to the industry. That being said, I think there is a tendency for organizations created around a cause to find themselves rudderless when that cause is finally achieved. The urge to not disband and instead look for another cause is often too strong, even if they don't feel quite as strongly about the new cause. I genuinely would like to know how traditional unions obtained their negative stigma. My guess is they were started with equally noble aims.