Interest is an increase in price*. Lower interest isn’t a discount, it’s a smaller increase. Calling it a discount is like punching you instead of stabbing you and calling it nonviolence.

*In exchange for better payment conditions, but that’s not relevant to the point.

“Better” doesn’t tell the whole story. There are hundreds if not thousands of different technologies involved in making an electric vehicle, from material selection for the frame to batteries to all the different components, software, conforming, etc. BYD cars may be overall superior to Tesla cars (I don’t know if they are, both are above my budget) but that doesn’t mean that there aren’t two or three hundred little things that Tesla cars still do better.