No telling what the future holds, you can only go with info you currently have. Cell decay is irreversible, AA's massive retirements = enhanced furlough protection and movement into WB FO or NB CA. Previously mentioned balance sheet and debt concerns could be a concern regarding AA, especially with its non-domestic exposure and increased foreign LCC competition. A recession would likely impact AA more than SWA, but to what extent is anyone's guess. SW is a solid, stable company and I wouldn't fault anyone for choosing them, but jerking gear in a B707-era relic to mostly domestic, less exotic destinations, for ~10 years isn't overly appealing to many, but they've done very well while others furloughed (or perished) during economic downturns (bankruptcy laws have changed since the days of UAL was allowed to exit). SW's single fleet type has benefited them enormously but the associated risks have 'come home to roost' with the Max; how this single source dependance on Boeing will evolve and how SWA responds (stay the course [likely], merger, 2nd fleet type, stagnation, etc) is yet to be seen, but this too will pass.

You'll know if you made the right choice on the day you retire. Best of luck.