Simply using the cartridge does not void the warranty, he says.

Or void the warranty on anything they own.

You didn't open it up and fool around with it because doing so would void the warranty.

Usually if a customer installs a different OS, it has a big impact on the PC and will void the warranty.

So why the stipulation that it needed to be replaced at 60,000 and the loose assumption that not doing that would void the warranty?

Apple has long been vocal against jail breaking, which if done voids the warranty on its devices.

Raspberry Pi has always allowed you to increase your clock speed without voiding the warranty just by editing a text file in Raspbian.