I don’t know. I set up a friend of mine who was a complete computer novice with Linux Mint on his laptop well over a year ago and he has not called me for support a single time, where he was regularly calling for help with Windows. People who are afraid of technology usually don’t go randomly clicking on stuff to see what happens. I’m pretty sure that grandma is safe. Plus, if you’re spending HOURS configuring a computer for an elderly person who likely won’t use it very often…you’re doing it wrong.
What I also do is create a complete backup of all of my computers to an external SSD with Rescuezilla on a semi regular basis, so I always have something to fall back to should the entire system or storage device goes belly up. 
I personally don’t store ANY data on any of my laptops. I use Nextcloud and sync the files I want access to on the go. The rest stays on my Nextcloud server at home.
If you are looking for a (mostly) fool-proof backup system that can restore changed settings and files even from a few minutes ago, you want macOS and Apple’s Time Machine. Pull out your wallet and hand it to Tim Apple.
I’m gonna have to go with the one on the left, even though the black level has been lifted a bit. I am looking more at the toolbar across the top and its functionality, which looks easier to use to me.
Doesn’t matter how sleek and shiny something looks if I don’t know how to use it.