It turns out he’s an Apple fan who relies on a Windows PC to store his media so that he can share it with his Apple devices. I would guess that it is quite common.
It sounds like your son has a healthy and open-minded attitude, I hope he enters the IT industry.
As will be evident from this thread, I am a devotee of Apple. But much as I like Apple devices, that 'like' is overridden when something else is more appropriate.
The Mac serves day to day desktop duties, and specifically iOS development.
We also have a windows box, which serves for alternative day to day duties or when we are both 'at work', and occasional dev, specifically when we need to see the world through the eyes of the majority of other users, i.e. windows.
As well as the Mac and the PC, we need a server as common storage, source control etc, media and TV recorder. That is a pure workhorse, doesn't even have a monitor attached, so Linux seemed the obvious choice.
And as well as the various iPhones & iPads, I also keep the old Android phone charged up, as once in a while I need to see something that's only available for Android.
I need and will maintain all of that. Difference is, and I know this is personal, the only kit that brings a smile to my face every time I pick it up or use it is... well, guess?