IT here. I use the F keys any time I have to change bios or bootloader settings, which is about once a month. Worst part is that no manufacturer uses the same F keys for getting into the bios/boot settings, and no bootloader either, windows and Dell change theirs over time. One Generation it's F6 to get into the bios, the next it's F8, and then a generation later it's Del. Sometimes it's F2 and F10 or F11 and F12; and almost never F3, F4, F7.

On a more positive note, Autodesk uses the F keys as hotkeys to toggle settings quickly, which is nice when I put on my drafter hat. I imagine a lot of technical software has figured this out.

I remember using F2 quite often when I was younger, but I can't remember why. I think it might have been New Game in a lot of the Windows built-in games?

That all being said... I get that these keys were originally intended for software to assign to whatever software-specific functions, as a kind of "Function keys," but we've evolved since then, and I much prefer the laptop scheme of having an extra key on the bottom row that modifies all other keys as a kind of "Function key" instead of 12 that don't do anything specific. Of the uses listed above, BIOSes/bootloaders don't have to use F keys instead of regular ones--except possibly standards requiring the other keys to always output specific characters even when the software can't use it, but if that's the case I'd love to see the devs all agree upon which keys open bios settings and which accesses the boot order menu.