I don't do houses hardly at all... but...
The last one I did (30 months ago) had the electrical work completed long before the appliances were delivered. The appliances were unloaded, moved into place, and plugged in by the appliance guy.
As luck would have it, I was there that day. While these particular appliances had cords that matched the receptacles I had installed, other comments by the appliance guy made clear two things:
-He considered himself to be some sort of electrical guru; and,
-He had no idea what he was talking about.
I see the EC as only being expected to put in the receptacle correctly. What's inside the appliance isn't his concern.
Folks want the stuff hard wired, well, that changes things. Then, I get to put in a disconnect as well.