This survey really doesnt say much.

first problem---they tend to survey people who may fly only a few times a year...thus their driven by price and fees.

Naturally southwest will score higher because of no baggage fees and all their planes are 737s. Casual travelers tend to book flights earlier when southwest tends to have sales but the other carriers do not.

They dont ask where respondents were from geographically. Some who disapprove of an airline have possibly never flown that airline so the issue is more with the lack of service then how the airline performs.