Oh boy, oh boy, your question is very exciting!!! I don't even know where to start, lol. There are 18.6M bitcoins, currently, and there will only be 21M bitcoins, a hundred years from now. It is estimated ~4M bitcoins (private keys) are lost forever
There's not enough for every millionaire in the world to own 1 single bitcoin. Adult population in the world? How about the whole world, what allocation for each country can have their own fair share of bitcoins. Microstrategy really screwed every US corporation out there by owning as many bitcoins as they can.
When you say all the Institutional Investors have owned as much as they want, what price of bitcoin would we be looking at? Woohooooo! Now you understand why there is so much
fomo among this investor class right now! They are panicking as they don't want to be left behind. A lot of really big investor funds have to wait for bitcoin to hit $50K price as the marketcap is too low for them to invest in, basically when bitcoin hits $1T market cap. You can front run those investors now.
Retail is PayPal, Square, Coinbase, Gemini, Robin Hood, and lately, you can get your salary paid to you in bitcoin like NFL star Russel Okung through Zap Strike, or you can use Bitwage
I just cannot fathom what price of bitcoin would be if as you say, all the big investors have bought all they need? Hint: there's not enough bitcoins for that to happen