I would think Boeing chopped the 757 because they couldn’t sell enough to get the profits from volume production and to steer customers to the stretched 737s (same way Douglas chopped the stretch DC-8 to help the DC-10…curious that they later did a re-engine program on 2nd hand DC-8s!)) .

Didn’t the wing modifications on the 737 Classic(300-500)…NG(600-900)….MAX always proceed incrementally so they were covered by the original paperwork and tests and isn’t the central wing box out to the engines the same basic design (obviously with thicker gauges/stronger alloys/modified cut-outs and strong-points for the landing gear and engines)?

Surely a 3rd-party re-engine program for 2nd hand 757s (like the RR Tay-727s program for UPS) would be more likely than a Boeing restart on the 757 if a suitable engine exists.

I read in Air&Space way back that Boeing initially only expected to sell a ‘few hundred’ of the 737 -300 series because UDFs were going to take over 🙂