We might be influenced by the stars, but we're forbidden to let our free will be guided by it. That would be against the First Commandment.
Note I said free will -- our free will overrides any "tendency" that is in us -- whether from genetics, the stars, our culture, environment, upbringing, etc. Those influences are very real, but they don't force us to act.
We are free, and deserve a reward/punishment for everything we do. That is, everything we do has a "moral" dimension.
But to answer your question, I doubt that Astrology is complete "bunk" -- why wouldn't the scam DIE after 6,000 years or so? There MUST be something to it.
But to a Catholic, it's irrelevant, since anything can be overridden with one act of Free Will.