The executives in charge at that point made a lot of money on the "90 Day Fiance" "franchise", among other badly and/or dully and/or grossly named things. IP and branding wasn't exactly their strong suit.
It wasn't bad because of the branding. If anything, the MAX name was kind of understandable since they ran out of hundreds they'd previously used to indicate variants and revisions.
Except the whole point of the fiasco is that this was a NEW airplane, not a refresh, but it was named and regulated like a refresh. That led to people dying.