I was mostly just reacting to suggestions that paper maps are unnecessary. I actually agree that you don't always have to be fully prepared against any possible eventuality, however unlikely. And that carrying too much stuff can be a hazard on its own.

I've walked hundreds of miles in England and I've always carried a map with me but I've almost always used the OS app and the paper was mostly for planning and getting a bigger view.

I am suspicious of electronics. This just seems like a case where, given the easy backup, why not use it when it might matter.