Boy, this is an oldie
I haven't seen one done like this since I took the photo, so I don't know the answer. It would fall under the POCO's rules. It was fairly common during the '70s and early 80's, but just in a few areas.
The semi-flush (partially recessed) meters, and panel boards are the norm here. There are nailing flanges meant to be nailed directly to the studs.
The photo is of a combination Meter, Main, and Panelboard.
Yes, we have have the service masts run through the structure. They are usually GRC or IMC, occasionally EMT.
SE cable is unheard of here. I've personally never seen a piece of it.