Is emulating human behavior really a valuable end goal though? Humans exist as the evolutionary endpoint of exhaustion hunting large pray and organic tool-making. We've built loads of industrial and residential automation tools in the last 100 years and none of them are humanoid. I'd imagine a household robot butler would be more like R2D2 with lots and lots of arms.
Every single behavior? For sure not but otherwise we are the result of a very very long evolution and there is nothing else around us as smart and as adjustable.
The planing ahead thing through simulation for example seems to be a very good tool in neuronal network based architectures.
It is when the world was made to interface with us. We can't use robots for everything if they aren't emulating us, because we would have to adapt everything for the non-humanlike robots.
We build our living spaces against the constraints of the human form, but that still doesn't imply the human form is optimal for anything. There's no reason a robot traveling over smooth surface should have legs instead of wheels or treads. There's no reason to have a head. Some kind of arm is a common design feature, but certainly no reason to have two. No reason to be symmetrical. A domestic robot may be constrained in terms of scale (ie see things at counter height) but not shape.
>We build our living spaces against the constraints of the human form, but that still doesn't imply the human form is optimal for anything.
We build just about everything we expect to interact with against the constraints of the human form, not just living spaces. And yes we because we built those spaces for the human body, the human body is by definition the optimal choice.
>There's no reason a robot traveling over smooth surface should have legs instead of wheels or treads.
There's a reason. The robot becomes useless for any surface that isn't smooth. What's it going to do about stairs ? You're not going to make a bespoke solution that generalizes for us better than 'feet that work'. Do you think it's better to built a million different complex robot bodies for every situation ? That defeats the purpose of being general purpose.
When we built self-driving cars, did we put a humanoid robot in the driver's seat? No. We put sensors on the car's perimeter and plugged in to the existing electronics. Forget "fits in human spaces" and think about an actual task you'd trust a robot to do for you before it's battery runs out. And who says you need one generalist? I have 5 different automated kitchen machines right now and they are all various types of rectangular prisms. I have a robot floor cleaner and it's a disc on wheels. I'd sooner have a kitchen robot that's on a rail bolted to the ceiling and connected to mains power.
This is a terribly contrived demo and not really realistic, but it illustrates my point. It's a bathroom-cleaning robot and it's kinda what I described. R2D2 with arms coming out of it's head. It's roughly human-scaled, but not at all humanoid.
The human form is not optimal, but it is general. When we want a general AI for all kinds of work, we can look to humans as inspiration, as we can do all the kinds of work we need, even if it is not optimal.
Of course, optimal robots will be useful, like ultimate roombas for cleaning floors or something like that, they will work better than humanoid robots for sure.
Really, the requirements are for the robot to move in predictable ways (if something looks like an arm, it ought to move like an arm, etc), and to have enough strength to be useful for difficult/tiring tasks while somehow also not being dangerous if something does go wrong.
