I will be the first to admit that the soft product in US airlines is not comparable to Qatar etc, but I would suggest you take a look at the total package, not just in the air but on the ground and telephone.
1. In the event of IRROPS (weather/mechanical etc) the US airlines will accommodate you faster/quicker. Check in agents are empowered to solve minor issues
2. Better IT systems,- I can waltz up to the check in desk and make changes on the spot- no going to a separate desk to process changes
3. Better on ground service if you are in the top tier- I have been accommodated on sold out flights (after a misconnect) and on one occasion a connecting flight was held for a few minutes so I could make the connection- the door shut behind me as I entered the plane

So it's not just about the pampered pooch treatment in the air......which at least within the US I would find somewhat cloying and artificial as it is not replicated in day to day interactions at work or home or in society generally