Paper maps are not "More accurate" necessarly but lets say the errors are easir to deal with
For example.. Years ago I had a minor "incident" as a result I needed to pick up a couple of USED auto parts.. So I drove to a junk yard using Microsoft Streets and Trips and my GARMIN GPS as the location source.
Computer showed me running through fields and over fences a good half mile from where I really was.. I do not know if this was GPS error or map data error but using the MAP I of course knew I was on a ribbon of blacktop.. Not some farmer's field.. and I got to where I was going.
But then I used that low-end Garmin E-Trex with nothing more than GPS coordinates to find the destination more than once. (no map at all,,, Just Brain).
Paper maps may be better at giving you Routing though.. The reason is they let you see more of the route at one time, and have indications of what kind of roads/goat trails you are routed on... Blindly trusting the GPS ROUTING can get you in serious trouble.
Also you may remember that tv commercical
TURN RIGHT (Drivr turns into flower shop) In 800 Feet.