Another "Offered job was Rescinded" post

So I applied for a job as a personal assistant in my field. Job was actually a lower level position than im qualified for with a significan pay cut. But I was really interested in the position and have been unemployed for a year after AI killed the previous company I'd been workong for.

Phone interview went well, met the individual I'd be working with and was offered the job immediately. Replied the next day that I'd love to accept the position. Got sent all the paperwork and tax forms and it was all approved- background check, medical approval, etc. Just about ready to start and suddenly they actually found a "better candidate" who's degree is the exact same as mine but they have a more relevant concentration.

I've worked 6 years in my industry and can do the previous candidates concentration very easily, but they can't do mine. I have just as many skills and the history to back it up. I don't understand why the job was rescinded when I literally had every task completed within a week. We talk about companies being horrible, but not even private individuals are capable of basic recruiting respect anymore! I hate it here!!