I'm confused by your question. The video in question is an entity walking in a simulator and not real life? There's a world of difference between what can be achievable in a simulator, and how to transfer that simulator learning to the real world.

Real world is messy. Lowering the sim2real gap is challenging. The sim above doesn't model actuator dynamics, overheating, probably doesn't model inertia correctly, joint friction, delays, etc.

I don't think anyone is having trouble making a robot walk. They've been very good at that for several years now. It's doing other stuff that's hard.

Very nice video. Comparing to the channel's latest, I guess the channel itself experienced evolution, with the Algorithm and clicks as its fitness function...

I think people can make robots walk, but it's really expensive and not particularly useful if most of what the robot does is walking.

It is very simple. Those are not real machines.