@purrperl let me also point out that the reason macOS and Windows are as popular as they are is because those are what students in school and kids that first interact with a computer experience.
The reason it is the first thing they experience is because Microsoft and Apple have tremendous amount of money to throw at that problem and put things in schools to indoctrinate children.
As such you have a society where fewer people grow up around a computer that is running linux, and you get fewer people that know linux, which means there are fewer teachers to advocate for linux in the classroom.
It is not because they are "easy" to install. It is because any computer someone buys from a major manufacturer comes with either macOS or Windows installed for them.
In the realm of advertising Windows and macOS are Coke and Pepsi, while linux is RC Cola. I fucking LOVE RC Cola,