Compared to the architecture of an OS targeting, say, hardware with native capability handling, Windows and Unix are virtually indistinguishable. They're both just "that ugly bag of compromises you make to abstract over a register machine that can peek and poke at an unprotected address space, with the OS managing an MMU through CPU-interrupt-triggered context switches to enable a kind of multitasking where each task perceives itself as living on a single core and is unaware of being pre-empted unless it checks for it after the fact."
There are examples of OSes that don't work like that, despite targeting x86. For example, bare-metal Forth.
No, because Windows has plenty of C++ on it and Microsoft Security Team advocates using C#, Rust and constrained C++ (Core Guidelines) as the future of systems programming on Windows.