Just what did you base this fantasy equation on, roughly?
Doubling a pilot's salary... Would the travelling public voluntarily agree to pay the extra money in the ticket price to allow this?
Generally speaking, no. (I know some here would disagree with this. And no, increasing the ticket price by $0.20 won't do it).
But the money must come from somewhere. Here is how it must be done:
Sack every odd numbered pilot and pay their salary to the even numbered pilots. The evens have now achieved the doubling of their salary.
But this would mean, of course, only half the number of pilots still flying - so there would be only half the number of aircraft flying.
So, the travelling public would be getting only half as far for their money (so as to speak). They would have to pay double what they did before, in other words.
As I said above, the travelling public would not accept this voluntarily. It would have to be forced upon them. How to do that?
Strike action.
Edited to add: Some here will not understand what I have written above. What I have said is: there is only one way to achieve immediate and significant improvements for pilots, and that is strike action. But that will put significant numbers of pilots out of work.