A fair share is defined in the bargaining process, anyone outside of the two parties involved saying what’s a fair share is foolish.
The logic pretzel the Democrats create is implementing economic policies that cause inflation.
The Union Workers pay is buying less and less because of that inflation.
The see big profits by the companies.
They also see the executives passing out big pay increases and bonuses to each other while they are living with a old contract that buys less and less due to the inflation.
They see UPS and others settling with their unions on nice new contracts.
They also see their jobs getting threatened by making cars that lose money while cutting back on cars that make money, like Ford and the F-150 and SUVs versus the money pit called EVs.
It’s the perfect storm of bad policies by the Democrats and foolish management which is creating this situation.
If you study the situation, it was inevitable a strike would happen, the big issue now is who is going to cave first
As I always read in those airplane magazines, "You don't get what you deserve, you get what you negotiate."