6 years may be a _bit_ long, but I think it has probably been kept going longer than it otherwise would by the current AI bubble, after the EV bubble fizzled (while EVs are a real industry they no longer drive super-high valuations). The likes of AOL maintained very high PE ratios for some years during the dot-com bubble, as did Enron, say.

The big question is can Tesla find yet _another_ bubble to jump to after the AI one pops. Watch out for Musk starting to say the word 'quantum' a lot.