It’s all the consolidation. Airlines pretty much enjoy monopolies at various airports.
If you live in Dallas, you’re stuck with American. If you live in Atlanta, you’re stuck with Delta.
Trust me the mergers are no fun for the working level employees either.
Had a career stewardess in the family. She went thru several mergers in her 40 years.
In Dallas you can fly Southwest out of lovefield. The airport is nicer than DFW.