(I'm personally more on your side of the argument than not, but need to point out literal details of the "standard" that is under dispute)

the article says if we transported back to the early 80's people would have said "it doesn't run Flight Simulator", so what that would have meant?

the original Flight Simulator for the IBM PC--first independently produced, then purchased by Microsoft--booted itself directly from the floppy; meaning, you had to reboot in order to run it; and it had its own "custom operating system" or really no operating system at all, something more like a kernel, or just an app.

yes modern "PC compatibles" do have some means of running that old software, but it won't work out of the box atm.

You would presumably supply usb floppy drives on the way back in time, and then you'd be alright. And an ethernet NIC with 10base2 and AUI for thicknet, cause twisted pair wasn't typical that early.

Network booting PCs happened a lot later, but if the booter used bios calls to access the disk, you could probably netboot that too.