Unions generate a lot of individual anecdotes, whereas any benefits are far more diffuse. The stories of unions protecting terrible cops, teachers, and running up costs in construction / maintenance are widespread and constant.

If you've ever worked somewhere you couldn't change a lightbulb on your own, or carry a small box of materials to another building, plug in an appliance, or similar you quickly get a dim view of their value.

I'm not saying all are bad, but the bad ones...are really bad.