Airlines have between 13 and 25% of the total cost in wages. However a pilotless aircraft will only safe around 5 to 7% of those costs as that is the average cost of pilots in airlines. However saving that would be offset by an increase in salaries in the technical and dispatch department and quite likely in the legal department.
The recent strikes at LH were cabin crew strikes, a cost you cannot offset with a pilotless aircraft as long as the airline still wants to offer some kind of inflight service. To replace them with an automated firefighting and evacuation system is technically possible, however one has to calculate the maintenance and weight penalty, not to mention the healthcare and insurance premiums for the case of a halon flooded cabin full of dieing passengers.
And of course one has to bring down the loss rate of up to 50% to acceptable levels (commercial civil aviation has an incident rate of 10^-7).