While you’re technically correct, I use “Windows machine” as a short-hand reference, for the understanding of a general audience. If you’re technical enough to run Linux on your Dell machine, you’re technical enough to understand that you can use this charger with it regardless of operating system.

I’m not going to say “Non-Apple computer”, because that’s no more correct. It doesn’t support Microsoft Surface machines or certain Chromebooks, for instance.

Please stop using “Windows machines only” when you mean not apple computers because that is just completely wrong.
I’m pretty sure that I can use this charger with my Dell which has Linux installed. I don’t think that there is charger for laptops which actually needs Windows on that machine.