First off, let me assure you that American Eagle is not an LCC operation. And, quite frankly, the airplanes they are flying these days that come equipped with a F/C cabin are nice, comfortable airplanes. Not as comfortable as a 777 or 787, but comfortable nonetheless compared to what they used to have.
AE exists because there are markets we serve that are not large enough to justify mainline a/c--like GRK (Killeen, TX). This incident has nothing to do with AE as far as I know. Nothing in the article said that AE was involved.
Now, what we know from the article is that the field trip to Washington D.C. for the kids had been in the works for almost a year. Company only told the chaperones that the flight had cancelled and there was no replacement airplane available. A company spokesperson said later that the cancellation was due to the weather. Now, granted, that could mean that it cancelled due to weather at some station other than OKC and could not get to OKC to pick up the kids. But, the question is still hanging...the world's largest airline had no a/c available for a substitute, period, end of discussion???? It was just across the state of Oklahoma from the largest(or, used to be) maintenance facility for the airline. It was even closer to DFW, our largest operational station. And, there wasn't one single substitute a/c??? Yet, on the spur of a moment Delta could locate an available a/c and fly it to OKC from Atlanta. You are not going to convince the average reader that AA acted correctly. Sorry, the winner of this contest is Delta. Game, set, match. This sort of thing is strictly a PR (public relations) issue. There ain't nothing the company can say at this point that will change the public's opinion of the issue--which I suspect is distinctly anti-American Airlines for the time being.