The Tesla is still an impractical car for 90% or more of average consumers. It's still mostly a rich person's toy/fashion statement. That's OK though, if it eventually leads to something that is practical and affordable.
The original Tesla was only practical for 1% of consumers. If the Model S is practical for 10%, that's real progress.
Low cost and high reliability come from volume production, which creates a chicken and egg problem. Elon started with the very high end, and is working his way down as a method to gradually build volumes and develop experience and technology to eventually build high volume low cost cars for everyone.
Contrast that to the "expensive fat econobox" approaches the other carmakers tried and abandoned.
From one of his talks, they have planned their roadmap in three phases:
- Very high cost, very low volume car to start off with.
- Moderate cost, moderate volume car (Tesla S).
- Low cost, high volume.
As we can see, they have achieved the first two targets (with surprising success).
If you consider the 'rich people' argument, SpaceX customers are still going to be fewer than Tesla's for the near future at least. (Although, that is not to say the businesses borne from using SpaceX like bringing better satellite based services etc won't affect a LOT of people.)
Tesla's also doing drive trains for Toyota, for the electric RAV4. Which isn't exactly cheap (about $50k), but clearly not aimed at the status-symbol market.
(Tesla itself is probably headed downmarket as well; the announced strategy has always been to do prestige models first and then ramp up the volume.)
I think it's stupid to compare the importance of such projects, that can and will be done only by the people in the future, when they will see the effects of what we are doing now.
