We switched my grandmother-in-law over to Linux last year and the amount of support calls I've had to do has dropped to 0. All she does is use chrome to check her email, and occasionally edit a document. A majority of the time she phoned for me to come 'fix her computer' it was just a Windows update that had reset some setting, or was trying to get her to sign up for a Microsoft account before she could log in, or some other obnoxious crap that made her think that her computer was broken.

We put her on Debian with Cinnamon as the DE, and downloaded a Windows 10 theme. We even put the Windows 10 logo as the start button. For her, she has 0 idea that she's even using Linux except for the fact that her computer doesn't randomly "break" anymore. All this with the added benefit that I can do remote support far more easily now.

The other huge benefit is when other relatives come over and start poking and prodding, it's far harder for them to do any damage. A few times I needed to 'fix' things was because her 60 year-old son (who knows nothing about computers, but is a medical doctor so he must know what he's doing) would come over and install a bunch of scammy antivirus software, change a bunch of settings, then leave proclaiming that the problem was "fixed". Switching to Linux has helped at keeping his fingers out of the pot immensely.