You can add my experience to this. I don't have a computer that's been upgraded nearly that far, but I've dual booted windows+linux in a wide array of configura

You can add my experience to this. I don't have a computer that's been upgraded nearly that far, but I've dual booted windows+linux in a wide array of configurations and never had data loss. I've accidentally wiped grub when installing (not upgrading) windows, and I've had windows refuse to update unless it's on the first disk in the bios, but I've never had it randomly nuke a partition.