If I may, from my experience as a long time Linux user who went back to Windows because of scarcity of design software available for the platform,
I don't mean to be rude or anything but from what I observed the main problem of Linux could be Linux users themselves as there are too many conservatives who would not allow proprietary code on their system. That's what I see as the main issue. Aside from that everyone knows that Linux is much more robust, stable and secure than Windows or Mac but also less marketed than both which is why most companies cater to mainstream platforms to generate revenue.
It's true, that Linux powers governments, banks, schools and many other important institutions. Your websites run on it, your servers run on it, your phones use the Linux kernel, ATM contains software developed on Linux and I could go on, but again, the main problem I see is the Linux community itself. Mac is a closed platform, period. Windows same, which is why it's easier to target them.
The way I see it there are only 3 options:
get a Mac
run WINE, PlayOnLinux or a virtual machine with Windows
dual boot with Windows where you do your work on Windows and general computing for security and privacy on Linux