When the term Catholic is used with the capital ‘C’ it is generally understood to refer to those Christians in communion with the Pope of Rome. That’s pretty commonly understood. If you are going to get involved in serious discussions this is something that you ought to know.
That's not an opinion commonly held by the Roman Catholic contingent. They include the Orthodox as Catholic capital *C*.
So, take it up with them.
You are Catholic. You posted a Prot hit piece. My comment stands.