He sounds like he’s got some sort of physical problem with his shoulder and tendon in his forearm.

In the video he complains about the smallness of the keyboard causing his shoulders to be in a bad position. He also talks about the “bounce back“ of the keys.

https://www.cnet.com/news/taika-waititi-demands-apple-fix-th...

Would be great if Apple just ran with this and reinvented the keyboard. That might mean nothing more than an external split keyboard that tents, for example.