Most computers in Turkey come with FreeDOS preinstalled because there's a law that states all computers must be sold with an operating system. FreeDOS turns out to be the cheapest and easiest.
That's why you don't let people who have never touched a computer write tech laws. You get results like this.
The computer is not very usable without an operating system. I think it would be reasonable for the computer to have Forth or BASIC or something like that in ROM, like many older computers do, so that the computer is usable without an operating system (but that you could also install an operating system if you wanted it).
Linux drivers and certification is a whole lot of extra work and complexity compared to FreeDOS. Years ago, Nettops were sold with FreeDOS where the components didn't support Linux that well.
Russia has a similar law and yes computers with FreeDOS are also a thing. Alternatively, you're entitled to get a refund for the Windows license by having your hard drive wiped and license sticker removed.
That's why you don't let people who have never touched a computer write tech laws. You get results like this.