Bit inaccurate, isn't it..? No such thing as Greek gods and Roman gods... “Roman” gods are just your plain old Greek gods with fake beards, speaking Latin in a Greek accent, and wearing their togas in the Roman style... Should have used Greco -Roman gods for one door and something else (Egyptian, Babylonian, Norse... take your pick) for the other...
Early christians in Rome were a lot more polytheistic. Many of the saints are borrowed from Roman gods and today they still provide a polytheistic feel to some christian churches.
We were literally taught that in catholic school. Just like Jesus was almost certainly not born in 0 AD. It’s just not important to his teachings, but rather important during the spread of catholicism.
Plenty of good reasons to be critical of Catholic Church, but “They claimed saturnalia as their year end celebration because no one actually wrote down proper dates 2000 years ago and the Romans still wanted a festival in mid-December” is not a great one.
It is the syncretist of the pagan. You can still see it in many places of the world. They treat religion basically how Westerners treat tropes in entertainment. Oh you like that show? Check out this show that is almost the same! I have seen shrines that had crucifixes hanging next to a Buddha.