I've noticed on some SATA to 4-pin molex connectors that the "orange" wire is missing. I know the orange is a 3.3v wire. If the HD is capable of running without it, why is it on the actual SATA power ...

That’s not always the case, as there are some newer standards available for high-speed drives. But alongside PCIe and NVMe, SATA is still a significant player, especially when it comes to larger-sized ...