I was about to ask "What is it we expect from GPU companies in the next ten years? Why/how will they dominate computing/innovate in ways that we care/compute?"
you answered my question. I think now is the time to invest in Nvidia and any other GPU manufacturer as the ML/DL/AI field is on the precipice to explode computing in the next 15 years. (15 years happens much faster than you might think)
That said, NVDA's stock just went 7% down due to an analyst's downgrade (which in the long run is relatively meaningless), so if you'd want to buy NVDA stock and hold it long term now might be a good time.
Disclosure: I am long NVDA, and my stock picking track record is atrocious.
The stock price reflects the market's overall expectation of all future cash flows discounted to the present value - all the way out to infinity.
When you buy at stock, you are implicitly betting that reality will exceed those expectations.
So, you just said that massive growth is priced in, and the fact you hold the stock implies that you are betting on even more massive growth - relative to expectations.
The main risks to this thesis are that 1. DL could turn out to be a short-lived trend or 2. a new semiconductor technology emerges that is 10x better suited for DL/ML (Google's new architecture?)
I think brain-space is the safer investment if we are not talking about getting rich from the stock but enrichening the cyber-sphere from that which can be developed in the ML/DL/AI space...