Originally Posted by
CDKing
I just noticed this on the AS Site. They claim it’s because they are being too generous compared to competition and wanted to be sure our bags fit on all carriers in the journey
It's actually intended to alleviate a very common complaint among customers connecting to/from international and/or codeshare partners, where the customer is shocked to learn the carry-on they'd had no problems with on their AS flight is suddenly considered too large by the other airline for their connecting flight.
We’re changing our bag size allowance to make sure that your carry-on bag will be accepted aboard all the flights within your itinerary. This will help you avoid carry-on bag size conflicts and make connections with other airlines easier during your future trips.
There's no nefarious intent here, it's honestly just about trying to not create problems for customers down the line.