Scroll back to 677 to read earlier report and discussion. I think we will see more of this as the airlines come to see Bilt as a "credit card" partner rather than as a "rent rewards" program. I imagine that Barclays and Citi complained, and I expect that Chase is also complaining.
Yes, I think everyone will be keeping an eye on Hyatt after this, and to a more limited extent, United.
Bilt is far more known now compared to when the AA partnership launched three years ago; much of that undoubtedly is due to them moving the cobrand card from an unknown issuer to WF.
AA is also allegedly in the process of renegotiating their contacts with Citi and Barclays, so there are a lot of moving parts on their end right now. AA of course has made it clear they want to increase their cobrand card spend, so they have an incentive to force people onto their cobrand cards. And eliminating a competitor to Citi and Barclays may also help AA extract more value for themselves from the upcoming renewal agreements.