We are talking here about sin. The parallel with interracial marriage doesn't hold, it was never a sin.
Your use of the word 'we' (we grew up) implies that unless one agrees with 'you' (liberal, socialists) we are immature, uneducated and unfeeling, a modern form of Pahariseeism.
Cardinal Burke has nothing to do with this discussion which is solely about the sinfulness of homosexual behaviour. You are implying that his utterances are as mortally sinful as indulging in same-sex activity.
The slogan seems quite Christian until you describe what it really means. You liberals decide what is essential and non-essential, we agree and everything is fine after that as long as we keep quiet and leave you unencumbered in your task of secularising the Church.
The sin of Trivialisation?
If you think that the offence against God of Mortal Sin, and the loss of one's soul for all eternity is a trivial matter then I agree with you that such a trivialisation is indeed a sin, a very grave sin.