I noticed, that tires have a box-shaped hit box. Therefore, a tire cannot roll at all. If you place a tire upright at a slope, it will not roll down. If you drag it upright, you will notice that it seems to roll over the invisible edges of the box.
The box even allows you to place wheels that they appear flying, because only their hit-boxes are stapled.
In contrast to this barrels have a cylindrical hit box and can roll.
Find a slope. Get a tire. And play with it around. Place the tier upright. And from that position try to roll it by 45°.
One screenshots (I can’t show more, because new user restriction):