True, but it is also true that practically all the other companies, governments and NGOs in the world--the ones that do not have providing services over the internet as one of their core competencies--chose Windows and keep on choosing Windows.
There are strong economic incentives that keeps an OS or other piece of infrastructure dominant for decades once it becomes dominant in some sector of the economy--if that piece of infrastructure requires many specialists for its deployment and maintenance--even when that piece of infrastructure has major problems if a hobbyist or an individual were to install that piece of infrastructure on their personal computer.
>Linux will get the downstream security benefits of that.
Linux would be able to derive security benefits from that if Linus cared, but a reading of his writings on the subject reveals that he does not care much about security.
I'm using Linux to write these words--a distro I chose and installed. I am however aware that because I'm using Linux, it is significantly easier to pwn me than it would be if I were using iOS, Android, ChromeOS, MacOS or Windows, which used to be a joke security-wise in the 1990s, but which has become much better security-wise.
Actually I believe that Qubes is pretty good security-wise, but it is the only Linux distro that is.