To be honest I think this valuation is too low. Elon continues to eat the competition's lunch on a daily basis with new ideas and approaches to just about every industry he touches. The competition will be left in the dust once he straps some rockets on his new model Ts.
All the incumbents are slow, fat, and happy with a lot of inertia and management layers from decades of success. They became too fat and too comfortable. They all look old fashioned by comparison to what Musk is producing.
EDIT: Top comment is disparaging Musk's success here. I think in all honesty there are a lot of people who are envious of Musk so they will always have something negative to say when he or his companies are in the news.