Thing is that it took 10-15 years for the stocks of these companies to reach the same marketcap again.

That’s what people predicted bit, for example, on Amazon’s case it was less than 3 years because they just kept posting solid numbers. The thing which all of those companies have in common is that they stood out from the Pets.com types in having profitable revenue - they didn’t need a miracle to be profitable, only for customers to keep buying.