The reality is that whether Boeing choose to do a re-brand of the Max, the underlying airplane is here to stay. For this class of airline, there are basically two suppliers in the west - Boeing and Airbus. Boeing has about 6,000 orders for the Max, and Airbus has about 10,000 orders for the A320 Neo. Airbus is delivering about 500 planes a year. So let's say an airline bites the bullet and cancels their orders for the Max and goes to Airbus - Airbus won't be able to deliver for the best part of a decade at best. Meanwhile, it would be enormously expensive for Boeing to design a replacement for the 737 Max from scratch and it still has tonnes of outstanding orders. And that's not even considering the fact that these airplanes have a lifespan of 25 years.

So in general there's simply no replacement for the 737 Max. People will be flying on them for the foreseeable future unless something causes a massive drop in air travel.