IT shops have evolved silos that many of us take for granted. There are server guys, hardware guys, network people, etc. this generally works as each discipline can take many years to master.
It's only when we look within the individual silos where we see problems begin to form as the silo model is often duplicated again and again. Within the server world, admins are decided into windows and UNIX / Linux admins. Networking pros can get divided into router / switch. Vs firewall admins. The sub groups become problematic as they generally align the pro by the tool they use.
Defining pros by the tools they use is dangerous and does a disservice to the IT pro. Tools quickly change in IT. The new hotness is often overtaken within a few years. Hiring a "Windows admin" is great as long as your organization runs Microsoft's OS. But what happens if something different comes along? Can your company pivot quickly to it if you've focused your staff specifically on one tech?
I've been trying to find other examples where we classify a person's occupation on the specific tool they use, and I'm stumped. People don't hire a screwdriver pro, nor a hammer technician; we hire carpenters. For IT and the professionals who work in the field to evolve, the current mentality must be questioned.
Focusing on the tools only benefit the tool companies. There's a form of lock in that occurs when we limit the horizons of the people in an occupation. At their hearts, most OSes are the same. Most network devices move packets similarly enough to one another. Storage too generally works the same from vendor to vendor. In each case there may be some significant differences in the techniques / algorithms used between vendors with any one discipline, they all have the same fundamental principles under enough layers.
IT pros would do well to keep in mind that tools change quickly and that industry longevity isn't guaranteed, but it can be made easier by understanding the core concepts and applying them to multiple vendors' offerings.