Humanoids are Silicon Valley's horseless carriage. The purpose of robotics, and tools in general, is to do things better than we can given our human form and cognition. Tools take on forms that are optimized for their intended purpose. A humanoid has no market fit because it's necessarily bounded by most of the same limits we have.
The point of a humaniod is compatibility with systems that have been built for humans, which is...nearly all systems that have been built. Environments and tools that exist in the world are ones that have been built for humans, so for a single robot to be able to interact with almost all of those, that robot needs to be shaped like a human.
Okay, maybe that's a special case. Maybe we should think of a task we haven't solved yet, like folding laundry. Why would a laundry folding robot need legs or a head? Why limit its arms to articulate only at the wrist, elbow, and shoulder? Why limit it to only two arms? Five fingers?