I arrived at Malpensa from TXL last week on AZ and it was a mid-field, stairs and bus kind of thing. So I am not sure how they handle a wheel chair there. At home at SJC terminal C, they have a truck with lift much like a catering truck and use the galley door. Used to be a wooden box mounted on a forklift. Thank god they got rid of it. Occassionally NRT will be a mid-field arrival too.
Really never saw a queue at NRT security. The immigration control lane has those tight turns so they must push a wheel chair thru the side gates.