No, those wouldn't be load bearing. Although, none of the ribs are really
"load-bearing" in the traditional sense of the term. Airstreams are monoque construction, so the whole thing is supported by being tied together...not just on the ribs (columns) as in stick construction.
Some "ribs" or vertical channels are there as backers or vertical supports for interior cabinets.
Just curious, which trailer is this in? The layout may help me to understand what the pseudo-ribs are there for.