You don't have to be state of the art to be a bike company. Part of their appeal for me is that they aren't 'state of the art'. They use commodity parts which means that I think they'll be repairable for a lot longer, and they also cost less than half of any of the other brands you mention (just for context, the cheapest Giant e-bike powered by Yamaha costs more than double what a Rad costs, and has a smaller battery).

Kia makes cheap cars using less than cutting edge technology, but that doesn't mean that they are any less of a car company than Mercedes.

Sure, they cater to the low end. But, their designs aren't off the shelf (or aliexpress), they have a network of showrooms and shops, and most importantly there primary business is the selling of bicycles.