This is all true:
When I started in IT, the average sysadmin supported 5-7 systems. Back then I only had about 15-20 passwords. Now I (and my team) support 200+ systems/software/services and I have more than a thousand passwords just for work alone.
The complexity increase is enormous. A lot of people have left the field because they just could not hack it as the minimum cognitive ability required has gone way, way up.