Use a 365 day rolling average. You'll arrive at the same absurdity.
There's many companies that have their revenues flat or falling from quite some time which are still priced for insane future growth. Go figure.
Haven’t run the numbers, but I assume that you could take the S&P 500 over whatever timeframe you want, remove all the stocks that didn’t outperform bonds, and be left with a basket of stocks that wildly outperforms the actual S&P 500.
And that uncertainty should be priced in with a risk premium, the risk premium is nowhere to be seen.
For this market cap to make sense, Tesla would have to eventually become the dominant car manufacturer worldwide. And that just doesn't seem like a reasonable prediction, given that legacy car manufacturers are starting to figure out EVs, and newer EV-focused manufacturers are making huge strides.
I don't know when (or even if) Tesla's stock price will fall back down to Earth. The old saying is that the market can remain irrational longer then you can remain solvent. But I do know that Tesla's stock price is not a good indicator of how well they're doing as a car manufacturer.
(The 30% is just an arbitrary number)