Christmas trees are shiny and attractive to cats, which means cats will likely get themselves tangled in the lights, break ornaments, and knock the tree over. If you want to get a Christmas tree with your cat, you need to take precautions.
One solution is to get a special Christmas tree stand that lifts the tree up off the ground so the cat can’t climb it. (Good luck.) Another is to get a cat post that looks like a Christmas tree so the cat can wreck it all it wants.
The bottom line is that your cat will likely find a way to mess up your Christmas tree, but that’s okay since Christmas comes once a year but cats are around all year round.