Because they're not going to sell a ton of units. Economics of scale work against them. They need to at least break even, and not just on the parts and labour for the unit (which are already higher than they would be on a higher volume product all on their own) but also on the r&d, post-sale support and warranties, administration, etc.
things with bike in the name or being compared to bikes should have teh capability of being human powered. an e-bike that has no human power is an electric scooter.
This is pedal driven as well. You can see the driver using their legs in the video, essentially this is a very luxurious e-bike. It is both street and bike lane legal in germany, which requires meeting fairly strict limits in how "motorized" it is allowed to be.