I will suggest a simple method for estimating when the roboticization of the skies is about to take place:
Count the number of dimensions.
Expect the process to follow accordingly.
The last 50 years have seen a fairly comprehensive automation of small-scale transport devices that (in freedom of movement) are essentially 1-dimensional , such as moving stairs and elevators.
Right now - and for the next 30 years - is the time that wide-ranging 1.3-dimensional devices, trains and similar rail-constrained machines, will become almost fully automated.
Next in line are the 2-dimensional vehicles such as personal automobiles, lorries, trams, etc. Much can be learned from this process that will pertain to automating air transport. (possibly including 'don't do it').
Then boats and ships. Sometimes high-value and complex to steer, but much slower than aircraft....and only moving in 2.3 dimensions.
Then, only then, the air transport system. At the far end (from here) of the learning curve.