Oh, how we do get confused!
Educated speakers sometimes go overboard in their attempts to speak well: for a strange reason they make the most basic errors with “I” and “me.”
They know that “me” is the object pronoun, the form to be used for the object of a verb or preposition. They also know that “I” is the subject pronoun to be used as the subject of a verb. Knowing this, not one of them would ever say, “Mom called I for dinner.” Nor would they say, “Me called Mom for dinner.”
Why then do some very well-educated native speakers say, “Mom called my brother and I for dinner.”
Perhaps it comes from an attempt to be overly correct and proper. Maybe even a little self-righteous.
Myself, I am confused by it all.