Looking at scope clauses, I don’t see anyone budging on the weight and seat limit. The economics of the 50 seat RJ is what is driving its demise. But there are just too many markets that can’t support even the smallest mainline narrow body, which is the A220 and only being flown by Delta. The United Express CRJ-550 is a stopgap as it only is viable on routes that can sell enough premium seats to pay for the same fuel burn with fewer seats. American is using used 170s to replace the 145s. There are only limited numbers of them out there. Maybe this will lead to Embraer to push out an E2 version of the 170 as it looks like seat capacity and not MGTOW is more of the limit. With the improvements on the E2 it seems like the most viable option for a plane that fits in the small RJ class.

Mesa, Republic, and Skywest all already fly United colors and E170 series aircraft. It still doesn’t help operators of 145s though. I think the cost of Air Wisconsin and GoJet to change fleet would still kill them off.