Contrary to popular belief:
Because you say so, or because you have evidence to present? I'm gonna go with opinion 1.
CHRISTMAS WAS NOT A PAGAN HOLIDAY!
Except that it is a pagan holiday. There is ample evidence to show that one pagan holiday or another was celebrated around the end of december long before the ever was such a thing as christianity. If not such holiday existed before christianity then why were early christian instructed not to decorate a tree as the pagans do?
You see there is a trend that Old testament prophets will die on the day of their conception
And you know this how? It's not as if the bible is replete with the dates of the old testament prophets conceptions, births, or deaths. More over there is little or any information in the OT that you can pinpoin to a certain year for you to even begin to make those types of calculations. Modern medicine can't even pinpoint an exact date of conception, so how the fuck do you expect people to believe you can do that with people long dead if not completely fictional?
So Jesus died on Good Friday
You have yet to establish If he ever lived in the first place, much less the exact day of his death.
not count backwards like 9 months or so and it will be January 6 or so,
Pregnancies do not last 9 months exactly, I have for kids, and all of them were born at least a week before the 9th month, with one almost three weeks before. You cannot determine the exact date of conception by subtracting 9 months from the birth date, It doesn't work like that.
now with all these adjustments in the calendar and stuff all these past years it is actually December 25
The julian calender didn't differ by 12 days until 1900, long after the christmas was appropiated by the church. Moreover christmas is not said to celebrate the conception, but rather the birth of Jesus. Which also conveniantly coincide with the supposed birth of Mithras (by a virgin no less), Saturnalia, and Sol Invictus, Day of the Unconquered Sun, both of which constituted the majority of pagan religions in Rome around the time of the Roman Empire's adoption off christianity as the state religion.
If you want to nitpick, then yes, christmas is a christian holiday, but by and large it was appropiated from pagan cultures that assimilated into christianity and has not so much as a single shred of biblical basis. Pagan traditions like the Yul Log, and the christmas tree, and countless others were staples of pagan winter solstice holidays in different parts of the world which gradually overlapped and spread into the christmas traditions of today.