Because the thing people refer to when they say “linux” is not actually an operating system. It is a family of operating systems built by different groups that are built mostly the same way from mostly the same components (which, themselves are built by separate groups).
I was shopping for a new vacuum cleaner when a saw a portable carpet cleaner. Basically a vacuum with a precision nozel bolted to a water sprayer. It has been a complete game danger for cleaning up the mess my cats would sometimes leave. Although it is still not as effective as the course of dewormer their vet prescribed.