[fsckboy]

There is economic inefficiency in many aspects of real world markets, so while a perfect world might be better, we don't have access to that. The problem with "restricted" float is that all the demand for investment (in that company, in that sector) cannot be met except by price inflation. But the market will respond by setting a market price for the investment and a market weight for that investment, and we must assume that includes skepticism and risk of dilution factored in, and from that point MPT says you want that weight in your portfolio, even though there might hypothetically be more desireable scenarios that are not available.

(now, large growing companies need public investment in order to grow, so it might be said that there is some value to regulations as a cudgel, "no access to public capital markets if you don't open yourselves up more," but again, we can still rely on market pricing once decisions like that are made)

NVIDIA is something like 8% of the S&P 500, and these companies are projected to be higher: you can't ignore sectors like that if you believe in diversification to squelch unrewarded risk

[im3w1l]

If you try to buy more shares than are available, then price will go to infinity which is clearly disastrous. That's in theory. But maybe it wasn't that bad in this particular situation?