By the time they can replace pilots there will be so few people left in work that there will be no demand for air travel so its not something to worry about.
But one could have a single pilot on board and a back up on the ground which some might go for but then there are still a lot of costs left compared with removing all human crew ON THE PLANE.
Aircraft could be remotely controlled and even if fully automated would still need lots of data fed in by airline ops departments and that intervention could always be a legal escape route for manufacturers. The cost of providing a warranty to the airline that the plane would seldom go wrong and if it did it would be supported by the supplier would be huge and of course that would be passed on from supplier to airline so many of the savings would actually never occur being transferred from column A to column B.
As for those fine people in the City they are simultaneous the lifeblood and poison in the veins of society at the same time and as their work is increasingly data based they are close to replacement by algorithm than pilots are