My Grandma is happily uses Linux. All she cares about it being able to get to email.
My Parents actually asked me to switch them back to Linux because they kept having troubles with Windows 7.
My Uncle uses a Chromebook, because they are really hard to screw up and easy to repair.
Encouraging the people I know to switch to Linux has dramatically cut down the number of times I get asked to fix something. Something like Linux Mint just works and tends to be more responsive. It also doesn't have Windows' bad tendency to demand that you restart because it just installed updates.
On the flip side, there are plenty of people I would recommend Windows or OSX to. Normally it's because they need/want to use an application that just isn't available under Linux. I feel like the learning curve for casual use for someone going from Windows 7 to Windows 10 might actually be worse than going from Windows 7 to Linux Mint, Ubuntu, or OSX though.