The question I have is if it is completely reasonable for BTC to reach $1 million (and I believe it is), why is the price so low? Banks, institutions, investors, hedge funds, venture capital, etc. should be buying up BTC like there's no tomorrow. I guess they just think it's still too risky? But plenty of businesses are already accepting and using BTC. We are long past proof of concept. The only possible tweaks that still need to occur are in security (exchanges & business, not the network itself) and ease of use.
My guess would be that your theory is spot on. We talk about super high values for bitcoin, but banks and hedge funds are very rational actors and are far more interested in a sure fire 2% bond than an extremely risky unknown currency asset. As much as I believe in bitcoin I would not vote to include it in a managed portfolio if I were on the board. Perhaps I could be convinced to go 0.1%, but anything else could be argued to be a failure of fiduciary responsibility. If it tanks, the whole board could be sued for this.