please consider.

When I crouch and have empty hands, I can open a gate.
When I crouch and have an item in my hands I can't open a gate.

When I stand and have empty hands, I can open a gate.
When I stand and have an item in my hands, I can open a gate.

So the behavior is not consistent. I don't see why that one (out of the four scenarios) bars me from opening a gate. If anything, to make it consistent, make it so I can't open a gate if my hands are full whether or not I'm crouching.

This is why this behavior seems like a bug.