Simply much less handflying, because it is a matter of spreading of attention.
What is the ue to fly manual during the climbout from 10000 to 40000 ft?
Only bit of nose up trim, a bit later a bit of nose down trim, then a bit up again..
What is the use of that? Cruise is the same story; why put all your attention in this? This is why you have automatics; on top of it its more comfortable for the pax to let George fly.