Prices for both companies are already very forward looking, and assume best case scenario of insane growth for at least a decade while assuming no risk or competition.

But tech is also one of the fields that is more prone to disruption.

Nvidia is consistently one product away from it's competitors to eat highly into their margins.

Google may have a stronger moat. No company in Italy I'm aware of is using anything but copilot or Gemini/notebooklm (talking legal, insurance, etc, not tech) because they are natural extension to the cloud and Microsoft 365 existing plans.

Recency bias seem to push investors to ignore those risks and plenty reason like you: they use recent hindsight to project future growth.