If other airlines Jet2, Easyjet etc are smart. They should hire almost exclusively pilots from Ryanair.
They can't beat O'Leary on price but they can take a very valuable commodity off him, his experienced pilots. They need to go for the jugular now that a weak spot has been exposed.
He will be forced to improve the T's and C's of his own pilots to stop the exodus. This can only be good for everyone in the industry. A rising tide lifts all boats.