Also because folks assume that the OT belongs to the Jews just as the NT belongs to the Christians.
I think that would fall under the ignorance column.
The Early catholic Church had the same Old testament as Jews from 70—90 AD
Catholic church still has the same old testament today!
Yes.
I always tell people who say “well that’s just the Old Testament” do you believe God is schizophrenic? He says something in the Old Testament and then changes his mind and says something different in the New Testament? Even Jesus said that the old laws were still valid. God does not change his mind. Whatever he says is forever.