Is it not just evolution/modernisation that is driving this ? The fact that the automatics are essentially controlled by mini-computers doing thousands of repetitive [and error free one should hope ?] calculations with minor variations to change pitch, bank, rate(s) and so forth ? A good example is a precision hold.
I'm sure many here remember times-tables ? and indeed I'm one of those old cranky Victor Meldrews who were not allowed to take "calculators" into exams back in my youth ? But what real worth is memorizing times-tables for the modern student, when a calculator is now a fundamental part of his tools ?
Likewise, modern pilots are expected to not only have the basic stick 'n' rudder skills, but also be able to manage the automatics and know [to a fair degree of certainty] what the raw inputs would yield without the computers ? Same deal with modern Jet Airliners, the automatics are a fundamental part of the aircraft.
I guess its the way its going, for example, you'd be hard pressed to find a manual FX trading (excluding futures, because no one can tell the future, not even computers) desk that can do as well as a comptuerised one, the arbritrage (price difference) exists for a millisecond [well a few hours or so at any rate] across markets and the ripple is almost in an instant globally equalized, all of this is done by computers with little or no input from a person, 24/7.
Which is why the banks make lots of lolly on our holiday drachmas!