Microsoft DOS and then Windows have gone through several evolutions over the years. When Windows first arrived, it was a User Interface (UI) shell on top of DOS. Then Windows 95 absorbed DOS to create something new — but didn’t include security. Windows 8 tried to absorb the smartphone experience, failed, but essentially made third-party anti-virus software obsolete.
Windows 10 took security a few steps farther (and integrated a better digital assistant, Cortana, that few people ever used). And now, with Windows 11, Microsoft has begun to integrate hardware security without integrating PC firmware (BIOS). Due to issues with the move to Windows 11, I think the next integration will be BIOS.