Why does it need to be rebellious? Sounds a little childish. Just roll with “happy holidays” or whatever and celebrate and let others celebrate whatever they want. Celebrating at this time of year has nothing to do with Christianity really, it’s much older tradition.
Do you think you’ve posted anything that would be worth removing in the first place? Seems pretty unlikely, so could be just a case of deleting your account and moving on. Unless you went around posting stuff that could get you in trouble and left in easy way to connect that to you in other ways, I don’t see why it matters.