[Santosh83]

It's not even this. It's just that for vast majority of 'average' people, they just use whatever OS comes with their devices. "Installing an OS" is an alien concept for most people. So it is automatically either MacOS/iOS or Chromium/Linux (Chromebook), Android or Windows. That's it. And although Linux the kernel features in two of these, that's totally beside the point. The point is people mostly don't even know how to change their preinstalled OS, no matter how irritating it is. If it develops too many issues, they take it to the local tech shop who almost always will reinstall/reset the same OS and give it back.

The only people who use Linux are the tech oriented crowd, including gamers, who naturally tend to be more tech oriented than most. This is still a very small fraction of the world though. And this isn't changing unless a healthy fraction of devices and PCs come with Linux preinstalled. Even then a lot of people will complain and ask for Windows (or whatever) the very next day after purchasing their device.