If the only electronic navigation system is a single chartplotter, then backup paper is essential.

We have used only electronic (mostly Nobeltec) since 2004, and gave up buying paper charts before crossing to Europe in 2008.
However we have two nav systems running on each of 3 PCs, and now an iPad with separate Navionics charts (dirt cheap and as good as Nobeltec or Navionics plotters) The iPad updates every few weeks. at no cost.

We also have an old Garmin GPS with a world chart, which would be enough many places when coupled with cruising guides for local port entry.

Thus, we have lots of backup, so see no value in paper charts.

Computer backup is cheap today. MUCH cheaper that paper charts if you are cruising any distance (e.g, a full set of charts for this year's Norway cruise would be a few thousand dollars)