Comparing the number of accidents & deaths caused by 'pilot error' on old-school aircraft with the number caused,or contributed to, by automation may yield interesting (and disturbing) results.
People have already done it, you can even do it yourself. There is some truth in it, but only some. It is indeed true that percentage of 'human error' accidents (as
percentage of all accidents) increased comparing to old aircraft, so human errors indeed take a larger share of all accidents today. However because of vast difference between absolute numbers human error accidents as
percentage of flights are still significantly smaller today. But ultimately customer doesn't care what is the cause of an accident, he/she wants to know chances of survival during a flight - and this is like 2 factors better today than say in the 60-ties.