> The sad days of DOS. Any program could peek and poke the kernel, hook interrupts, write anywhere on disk.

Sad? That was the best part of DOS. Some of my fondest computing memories was on DOS - warts and all. Being able to live hexedit your drive and memory to cheat in games, the sheer freedom you got from hacking around the OS is incompatible to modern operating systems - even Linux.

You were in full control of your computer and you decided how it could be used, not some mega corporation or compliance agency.

DOS wasn't sad, it was fun.