Except in the case of a person being baptized as a Baptist, who doesn’t become a Catholic as a result. This is demonstrable by the fact that if the same person shows up later in RCIA, they don’t have to be re-baptized but they do have to attain union with the Church before they can receive Holy Communion. Baptists cannot just waltz into Catholic churches and receive HOly Communion without going through RCIA, baptized or not.
I am aware of this. This is not what confirmation is for. Moreover, what makes someone truly Catholic may not have anything to do with a particular sacrament.

[Maybe some Catholics are not aware of how many non-Catholics visit Catholic churches and get into Communion lines without understanding what they are doing. Happens all the time and twice as often on Christmas.]
In the Latin Rite, it is true that infants don’t receive Holy Communion. Not the case in the East. Infants cannot consent also, so not sure how this works. Perhaps they receive at the behest of their parents, in whose care they are until they can consent.
Yes, this is the Catholic opinion, but not the opinion of non-Catholics. The OP does not hold this opinion, so it’s rather pointless to tout it to her in a forum. She doesn’t believe it.
Bingo! Now, we’re getting to the point, by whatever you want to call it.
Nevertheless, to quote you, “she has the ability to choose to accept her Catholic faith or renounce it in part or in whole.”
You can tell better than she can what she intended…in an internet forum, yet? I doubt that.
I really do think that infant baptism can have some of the properties of forced conversion. For that reason I personally think that it’s possible for a person to choose not to be Catholic as an adult. And I think that should be respected.
I also think that Catholics make a huge mistake desperately trying to hang onto people who don’t want to be Catholic. It’s not right because people can “the ability to choose to accept her Catholic faith or renounce it in part or in whole,” as you said above. That’s the meaning of assent.