Well, you said it yourself. Pinnacle was in bankruptcy. If they had no union, management would have screwed them even worse. The fact is that Skywest management gives you enough to keep you non-union. The mere fact that others are unionized and Skywest isn't, helps the skywest pilots. Thus, that's how you they ride the coat tails. Everyone else is trying to fight for better with intransigent management.
You can't have it both ways. If unionized pilot groups have NEVER helped the non-unionized ones, then you can't blame the unionized ones for bringing down the non-unionized ones.
PS. Even though you conveniently ignored it, I'll say your welcome anyway.