AmosTown, that the saints exist, that they can intercede for us before God, and that it is proper to ask (pray) them to do so are all firm Catholic teaching.
Disagreeing with these teachings doesn’t automatically make one a non-Catholic, though it does make one a disobedient or dissenting Catholic. It’s very hard to actually stop being a Catholic after baptism.
I think what people are saying when they say that a Catholic is not required to practice devotion to Mary or the other saints is that additional, private devotions are always optional and up to the individual. No one is required to wear the various scapulars, for example, or even to pray the rosary. That doesn’t mean that one is permitted to disregard the teachings of the Church or to refuse participation in the public prayer of the Church.
Usagi