Practically speaking you either need to be someone with a great deal of linux knowledge or have reasonable access to someone who does.
Let’s face facts - when something goes wrong (and it will eventually - for example when I upgrade Fedora issues large and small are not unknown) you will need to noodle it out. Or for example just getting something like Pipelight (the linux Silverlight replacement) working. The average user isn’t going to be able to deal with problems over a certain complexity.
Windoze and apple will also have issues with their OS’s but there there is paid support model that people can avail themselves of.
With linux it’s figure it out yourself (usually with the help of Google), or ask someone to help you.
Don’t get me wrong - I love linux and use it all day every day. But to pretend that grandma or aunt millie can just hop on linux and use it effectively - no.
Yes, you can run into some issues when attempting to install/configure software that most people don't use. I've never installed Pipelight, so I can't speak to that, but expecting grandma or aunt millie to do so is just wrong. Heck, I doubt they can install Windows.
Once it is installed, I do fully expect that they can "hop on linux" and use it effectively--for them. That use case is pretty much just web browser and (possibly) e-mail. Those are no-brainers.