Yeah I noticed that as well. I guess it IS intentional, as it seemed like sphere or capsule collider was used instead of box collider.
The thing is, I feel like I understand why that is helpful. If the boxes used box colliders they would get permanently and easily stuck in corners and be difficult to get into narrow passageways.
I guess the best solution for this problem would have been using a GRID system, in which all objects moved in fixed steps. The level design is already fit for that, and quickly tapping to move would have made it feel more like a strategy game rather than one with wonky physics simulation.