That's sadly true though. Also booting something was really simple.
replyNow we boot an embedded microcontroller (or CPU) which boots the main CPU which boots another OS semi-persistently to boot the main OS (if it's allowed).
Sometimes there are other processors needs to be up to allow processor to continue booting as well (these are mostly servers, but eh).
You can still have the 90s OS experience, even today, but these days we use the name bootloader, not operating system, for that amount of functionality.
replyExcept in the 90s, I could wield my OS of choice on the hardware I bought.
replyWhat OS could I have loaded onto my Macintosh SE/30 that wasn't from Apple?