All of the things so far cited as ways Boeing has been obfuscating the MAX name have been things that Boeing has not actually done. On the contrary many airlines are being clear what they are doing to bring back their MAX aircraft, and not trying to hide it.

The -7 -8 and -9 designations have been used since the beginning. The -8200 is a special high capacity -8 with extra exits for a really high density 200 passenger layout that RyanAir wanted. The MAX name is a generational marketing name like how the -700, -800 and -900 got named "Next Generation" and the previous generation named "Classic" at that time.

Renaming it is not going to work and would not inspire confidence, and Boeing knows that.