My impression is that a big part of the reason for the sudden boom in humanoid robots is that they lend themselves particularly well to RL based training using human-made training footage using VR. It’s much easier to have a robot broadly copy human actions if the robot looks like a human, instead of having to first translate the human action to your robot arm equivalent.
That is certainly a factor, but you also have to take into account that all these tasks in the factories are now centered around the human form because humans are doing them.
The big part is the rise of modern AI in general.
The success of large multipurpose AI models trained on web-scale data pushed a lot of people towards "cracking general purpose robot AI might be possible within a decade".
Whether transfer learning from human VR/teleop data is the best way to do it remains uncertain - there are many approaches towards training and data collection. Although transfer learning from web-scale data, teleoperation and "RL IRL" are common - usually on different ends of the training pipeline.
Tesla got the memo earlier than most, because Musk is a mad bleeding edge technology demon, but many others followed shortly before or during the public 2022 AI boom.