Yes, and this is insider info. SWA is a point-to-point airline. They are not the far more common hub-and-spoke. This requires not intensive following and scheduling. They have a system to do this but it is underpowered, archaic, and has known flaws.
The flaws in the system have in fact long been known. There have been lesser but similar meltdowns before. The pilots union asked the company to make necessary corrections many years ago. They were ignored. Why? Because correcting the discrepancies (1) cost money (2) suggested restructuring (3) offended the sensibilities of certain stakeholders who perceived a threat to their importance (and their fiefdoms).
Executive managers have been weak and tentative, not solving neither the insufficient IT, nor the restructuring problems. The result has been chaos. This would NEVER HAPPENED under Herb Kelleher, RIP, but he’s long gone.
Hope this helps.
You stated Southwest’s problems very well.
The CEO, key employees and the board members of Southwest all ought to be forced to resign. This is a colossal failure of responsibility, given they all knew there were issues with legacy IT systems.