Listen to Farnborough LARs any weekend and hear the people without charts asking a busy LARs controller for the freq for Headcorn/Stapleford etc because they can't read a frequency off their yoke mounted GPS.
The bloke last year near East Mids whose GPS had packed up, and he was lost without a map, or the guy who bust Doncaster airspace because although the half mil showed their new airspace, his GPS didn't.
A current half mil is always folded to the correct place in my cockpit and has lines drawn on it.
SND