I know I’ll be blasted but our cat, a 14 pound desert lynx/domestic cross named Bob, spends time every day outdoors. He’s always home when it gets dark though. He never troubles with the Christmas tree since there are no end of trees outside for him to mess with. My dachshund on the other hand, immediately started rolling up to sleep in the tree skirt. We ended up putting his bed under the tree (behind it) with his favorite blanket. Then we piled presents on the tree skirt and so it’s all good.
Our cat (also named Bob) gets outside almost every day, as well. His main reaction to the Christmas tree has been to seem alarmed about it, but to try to come and get me to “show” me that there’s a tree in the other room. Then I assure him all is okay, and he seems good for a day or two, then repeats the alarm scenario, like he forgot about the tree and just found it again. But he hasn’t touched the ornaments or tried to jump onto or into it (at least none of this has happened when we were around, and there has been no evidence....). :)