OK ... then nobody lied to you, and I wasn't talking about you personally.
In addition, the Congregation for Divine Worship and the Discipline of the Sacraments, confirmed in 1994 that service at the altar is one of the liturgical functions that can be performed by both lay boys and girls. If you believe that the Pope is Peter’s successor and the primacy of Peter, then how can a girl altar server be a “lie” when papal-approved Canon law allows it?
OK, it's a prudential judgment, by the Pope, and therefore warrants respectful consideration. Upon respectful consideration, I consider the decision to have been unwise. I note historically that those who pushed for girl Altar Boys were the same folks as were pushing for female Priests. That alone is cause for suspicion. To the extent that being an Altar Boy is (perceived to be) a first step toward the priesthood, allowing girls to take that first step is lying to them. It is telling them, implicitly, that one day (when the Church is more "enlightened") they too may be ordained.
I was an Altar Boy from about age 8 to about age 18. I was never asked if I wanted to be a priest (surprising, in retrospect). I thought about it, but did not have that vocation. Still, there was a pervasive understanding that while not all Altar Boys become Priests, virtually all Priests had been Altar Boys. First step? I think so.
Canon Law permits girl Altar Boys. Therefore, they are permitted. The decision is above my paygrade. It is, however, not a doctrinal definition and I am free to think it unwise.
Pope JPII must have thought the same thing. Two months after the Congregation for Divine Worship and the Discipline of the Sacraments clarified Canon Law about girl altar servers, the Pope issued his statement that men-only priests was a matter of Divine Law and this CANNOT be changed. He drew a line in the sand.