There’s been only one real purpose of v6 that I’ve seen being the reason to switch: v4 running out of available addresses. Never seen anything else about v6 being used as any kind of reason to switch. So the only reason we’d ever go over to v6 is because we have to, not because we want to.
Isn’t almost any keyboard able to last that long?
I make sure any motherboard I buy has at least 8 USB ports, so I know I’ll have enough. It does make sense to use the PS/2 port if you have the peripherals. What advantage does USB have over it anyway?