It's not just that the world is built around human-shape, but it's also that humans are very, very adaptable. Our hands are a marvel of evolution allowing us to do extremely precise tasks while still being adaptable to all kind of movement : Screwing in, out, grabbing weird shape in 6dof, rotating along several axes, ... And ours arms, our legs, etc, have similar benefit. As an example, we are not a fast specie, but we can walk on even ground, rough ground, steep inclined, we can climb rock and more. If you see a place, you can probably go there.

This is why human are still used for many, many tasks, including in industry where a lot of things are handle by robot. Yes, you can have an automatic belt feeder, or moving tray system, to move pcb from the pick and place machine, to the furnace, to the assembly, etc. But it means your assembly line is fairly rigid. Accommodating a new process, a different size of pcb or whatever become a costly endeavor. A human on minimum wage can cheaply move things from machine to machine, check if everything is alright in the process, adapt to new processes, new floor layout, very easily and cheaply.

Robot don't need to be exactly human shape, but having robot with the same adaptability has human have a huge advantage for companies where adaptability is a core part of the business.

Most countries have laws like the US Americans with Disabilities Act meaning that there are enough ramps and elevators around that a wheeled robot can do pretty well. It actually is more about the training factor.

> but because the whole world is already built for human-shaped agents anyway

not really, there's several non-humanoid shapes that can easily adapt the human shape and to it but it's a little out of the box. you can imagine it without imagination, too, with a little thinking. it's just a few rational hops, really.