We have a small house, and just like all aging people, we have accumulated stuff. Up until recently we had just the right amount of furniture, but in the past two months we added cat detritus (litter boxes, food dishes) and we Gary added mitigation devices (Hepa shop vacs, Hepa vacuums, humidifiers, and full-size floor air purifiers in five rooms, no I am not kidding).
So, the house is a bit of an obstacle course to get through. There are several things that could be shifted to the basement (the standing globe, the step-stool chair) but Gary insists he loves those things and they must be within sight. I can't walk through the great room at night: there's no path. The computer room looks like a model of the solar system I made in grade school: no space between the planets, Gary's chair is the center sun, all the moons sprinkled through the voids.
And then to add Christmas to this? Not a chance. The hanging tree is staying in the basement and we can visit it if we feel festive. Besides, the tree blocks the ledge the cat likes to jump on. The only festive spot might be the porch, where the reindeer go, but honestly I cannot cram another object into my visual field. There is no negative space.
It's not at hoarder level, but add one more thing and it will be. My dad was a borderline hoarder, but at least he constrained it to one room.