The upside: Android users can enjoy group messages from family members on iOS properly, and find a cross-platform messaging app that avoids Google’s habitual develop-and-drop app releases (you know, where they tell us an app is the best thing ever then do the same thing a year later with something else, ala Hangouts and Allo… and Duo).
iMessage is also encrypted, so that’s a nice touch for Android users as well.
The downside: This rumor is based on input from “a source familiar with the company’s thinking,” which is as sketchy as it gets. Also, iMessage is free, so Apple really has no true upside for making it available to Android; one simple messaging app won’t make someone switch platforms.
If it’s true, we’ll be excited. If not, it’s days before WWDC, so what did you expect?