One thing is clear amongst all the scuttlebutt, the 737 MAX is a new type not an ng with a few tweaks and a slightly different cockpit layout.
Buying a new aircraft type is a big undertaking for any airline and expensive getting their existing pilots certified on the type while still operational on the existing 737 fleet. This makes it more difficult for Boeing to sign up customers for big orders so they tricked customers into buying the MAX by certifying the aircraft as a variant so that current ng type rating applied with only new cockpit familiarity checks.