The question isn't about current margin; the question is about long-term margin.
Running at a loss to build out market share, technology, branding and economies-of-scale is a standard startup strategy. Tesla is still in that stage.
The key question is whether things like the Gigafactory provide Tesla with unique economics and competitive advantage. If they do, Tesla will be able to have lower costs or more expensive products than GM. If not, it's overvalued.
