Your staff is too short. You’re digging in the wrong place.
Why is it that when people don’t understand something, they make up some bullshit to support their incorrect statements, and think people will believe it? It’s puerile, like when your kid tries to convince you they brushed their teeth, but their breath smells like dinner and they didn’t even bother wetting their toothbrush to make the lie plausible.
Did you really just count the 8 pins on the EF lens-facing side of the adapter and the 9 contacts on the EF-M camera-facing side and come to that simplistic and totally incorrect conclusion? ‘Reserved for future use’ is really the best you could come up with? Well, people make themselves look like idiots every day, so you’ve got lots of company.
With a modicum of initiative, you could have at least counted lens contacts. EF-M lenses have 9 to match the 9 mount pins, whereas EF lenses have only 7 contacts for the 8 mount pins. One of the EF lens contacts is double-width and bridges two mount pins together, that’s the analog ground. EF-M uses a single pin for ground, so functionally there are two additional pins in the EF-M mount. The mount adapter wires two of the pins on the EF side to a single contact on the EF-M side.
Of the two new pins in the EF-M mount, one is an electronic replacement for a physical microswitch in the EF mount to confirm full mounting of a lens. The other is used to signal that an EF/EF-S lens is mounted in the adapter when it’s used.
The remaining pins have the same functionality for both mounts, although the order of the pins is different between them. Also, EF-M lenses operate at a lower voltage and higher clock speed than EF lenses. So no, it's not even close to 'literally straight through'.
Details on the EF-M mount shared above are described in its patent:
The camera side mount is brought, by relative rotation with the accessory side mount, from a first state where each accessory side bayonet claw is inserted between the camera side bayonet claws into a second state where the camera side and accessory side bayonet claws engage with each other. The...
patents.google.com
The right thing for you to do here would be to admit that you were wrong. Go ahead...surprise me.