Yes, Christianity civilized many people. Without question.
Interestingly, I was reading that the Romans almost never persecuted anyone for merely being a Christian (a few exceptions).
They persecuted ANYONE who didn’t pray to the official gods for the empire.
The only exception were the Jews who had early been friends of the Romans and the understanding is that they Jews would pray TO their god FOR the empire and emperor.
If you were accused of being a Christian the first thing the Romans would often do would be to give you a chance to get off the hook by making a sacrifice to the Roman gods, if you did, they let you go.
NOT sacrificing to the gods was considered treason and something that would bring their wrath on everyone.
That is the reason that the whole controversy over were Christians Jews or not was so vital. If they were a subset of Judaism it was one arrangement with the Empire, but if you weren’t a Jew and wouldn’t sacrifice THEN you were a traitor. The Romans didn’t care who believed, they cared about who obeyed. There were exceptions, but overall even if someone accused you of being a Christian all you had do to was make a small sacrifice and they let you go. However, of course, the true Christians wouldn’t do so and thus hello arena.