Also, who cares? Sometimes products take longer than usual. Especially ones that have never been done before, like a practical electric semi truck for chrissake!
Plus, they also had to move a lot of people to rework existing models to accommodate supply chain issues from Covid for like several years.
BYD has shipped tens of thousands of EV semi trucks, starting in 2018, approximately 5 years ago. This is something that absolutely has been done before, and is available for delivery today.
BYD is the second-largest manufacturer of BEVs and the largest manufacturer of the category that comprises PHEVs and BEVs. The company is not well-known in America, but Warren Buffet invested in the company way back in 2008.