why christians shouldn't celebrate christmas

That is a complex question with many different perspectives. Some Christians believe that Christmas is a celebration of Christ's birth, while others believe it is a pagan holiday that has been co-opted by Christianity. Additionally, there is the issue of materialism and consumerism that has become associated with Christmas in many parts of the world. Some Christians argue that Christmas has become too commercialized and has lost its true meaning, while others believe it is still a celebration of the birth of Jesus and can be celebrated in a meaningful way. Ultimately, it is up to each individual to decide how they want to celebrate or not celebrate Christmas.