This cathechism states the classic Trinitarianism of the RCC. So what. It is authoritative to American Catholics, but I’m not Catholic. For Protestants, official statements like this is reason enough to question it...and reject it.
I have examined it and find it seriously flawed. I reject it like I reject their other doctrines - Mariolatry, the alleged supremacy of the Roman Papacy over Christianity, Peter being their first alleged Pope, and a hundred other similarly false doctrines.
“I have examined it and find it seriously flawed.”
“It” being the Catechism? The Doctrine of the Holy Trinity? Something else?