Union decline is correlated with the collapse in standard of living, which is only held up by (or was) by cheap goods from Communist countries. Not a great thing to support if you value your freedom.

My wife is in a union, and is not strongly against them. In fact, they're the reason she makes a six-figure salary. She also has a robust contract to prevent abuse. I am non-union as a developer and am pretty much over a barrel. It's a no brainer to work in a licensed, union career for most people. The only losers are the owners.

I have been a manager in a union shop though. And had no issues with the union. In fact, companies get the union that they deserve.