I don't really understand why unions are the answer to what should be basic and universal ethical labor standards. Because, what, if you aren't in a union or u

I don't really understand why unions are the answer to what should be basic and universal ethical labor standards. Because, what, if you aren't in a union or unionized job you don't deserve to get treated decently? Because industries where unions and workers have less leverage should be able to treat workers worse? Or is the union thing just a reaction to lack of faith in other institutions? I don't hate unions, but I don't get them either. And I often suspect that structurally they're much more incentivized to containerize reforms rather than universalize them.