I should have been more precise here. Yes, modern Windows runs on NT kernel, which is actually very good: stable and relatively light.Windows 95/ME were built on DOS but Windows NT, the progenitor of modern Windows systems, was a fresh start that had a lot more in common with Digital Equipment's VMS operating system than DOS.
But NT took over most general ideas from DOS.
The way programs are installed and run, the idiotic directory tree, backslash in paths, stupid file encoding, different newline - we could go on and on. Windows is - in many ways - different from every other mainstream OS. And it means it's also super irritating for developers. Or even for casual coders (like financial analysts).
And while in the early 90s MS may have still hoped that DOS will rule the planet, shift to NT kernel happened when it was obvious that servers and mobile devices will run on Unix-like (POSIX-compliant) systems. But they were afraid to make the transition. And here we are, 20 years later. NT-kernel is at the edge of becoming just a fancy hypervisor.
I mean: being a cloud dev working on a Windows laptop, the only 3 tools I use for work that run natively are: VS Code, Chrome and Conda. Everything else is either remote, WSL or Docker.