1. I don't want pay banding based on job title, I am capable of negotiating this myself. This is especially true because I can remain at senior Dev level but based on contribution I can be compensated, not by title .
2. Historically there's evidence of damage to industry caused by unions.
3. The unionised work places I have heard about second hand, do not sound like places I want to work. For example unproductive employees not fired, promotions and internal job moves being extremely bureaucratic and check box oriented.
4. I do not want to be forced to pay union dues.
5. I do not want people telling me I must strike.
But I can tell you from experience - it's definitely not "one lazy guy" - it becomes endemic because the process for dismissal becomes so costly. It's extremely demoralizing working alongside people who are "working the system" and are lazy as fcuk. It's better to just leave.
Here in the US, corporations all over are making record profits! Buying back shares like never before! Unless you want to play definition games about what a "competitive market" is, plenty of companies in competitive markets have big pots of gold to hand to employees.
There's no pot of gold in most cases. But I still think there's a good case for unionization.
This typically translates to "the company's successfully lobbied for trade agreements that allow us to force our domestic labor to compete against impoverished foreign workers in a developing nation with nonexistent environmental and safety standards," which is a race to the bottom for everyone but aristocrats.
I think the problem in the US is that the country is deeply right-wing when it comes to labor policy. The union/management relationship in the US is designed to be adversarial. In Germany, it's legally mandated for unions to be represented at the board level, and that kind of cooperative relationship's results speak for themselves. Here, that idea would be considered tantamount to bolshevism.
