It might seem controversial, but isn't it just normal supply and demand. When there's a glut of pilots (as there has been for a few years), T & C's get squeezed down. When a shortage happens, things go in reverse, as airlines poach and are forced to offer better T & C's to recruit.
If you want T & C's to stay the same when there's a glut, then they need to stay the same when there's a shortage.
Skintman