This would be a supplementary tree. There isn't enough width here for a full-sized tree. For example, my in-laws have gifted my wife hand-made felt Christmas ornaments every year. They were clogging up our main tree, so she wrapped a traffic cone with some green felt and made a smaller, entirely felt-themed, supplementary tree.

Or you could have an inflatable or stuffwd snow man. Or Santa. Or the Easter bunny. For Halloween you could have a ghost hanging from the ceiling, or a zombie, scarecrow, cloaked figure, pirate, whatever. I actually have a Halloween Tree that's a black dead-looking thing with orange lights.

Of if you have cats, that's a great spot for a cat tree. Or one of those slings that hangs from the ceiling.

Or how some people collect those squish Mallows: that would be a nice nook to store them.

Obviously these are all luxuries, but I think from this picture we can assume this is a pretty big upper-middle-class house.

Everyone is in the back and you send the smallest child to pick up and drop off the presents.

Everyone Sitting in the hallway would be the worst part.