The writing's been on the wall for years now, starting with the actions of the Big 3. Anyone who hasn't become a free agent at this point is either tied into a corporate contract, or has a misplaced sense of loyalty. There's also the issue of being hub captive, which is why I flew almost exclusively with UA for over 25 years.
No offense, but with that kind of spend you wouldn't even make 1k at UA now, and even 1ks are realizing this game is a losing proposition. When most of the benefits can just be bought with a premium fare and redemption of miles becomes increasingly difficult, what's the impetus for that kind of loyalty?
I fly about 50% now on AS, 25% on UA and the balance on whomever has the best schedule and price. Enjoy your newfound freedom!