Vatican II was stealth heresy, perpetrated by people who had been heretics for years (decades?) before they showed up in Rome.
It is on thing to have a motto or aphorism which, because of brevity, might lend itself to ambiguity or abuse. "God is love," (St. John) for one. Or "Love, and do what you will." (St. Augustine.) "The glory of God is man, fully alive. (St. Irenaeus). "Why do you call em 'good'? Only God is good" (Jesus).
It is another thing entirely, to take an isolated ambiguous or paradoxical statement,and elaborate it into a framework of false theology.
That, I think,explains at least some of what happened in the aftermath of Vat.2.
Ooos. “Why do you call ME good? Only God is good.” - Jesus