Objectively speaking, once an ETF is available as a public investment vehicle, anyone who does not at least have exposure as a small percentage of a tax-deferred retirement portfolio is completely out of their mind. That alone is a monstrous amont of capital, total US retirement assets are on the order of $20 trillion. Capturing just one tenth of one percent of that would be about $20 billion slamming right into the float.
If 20 billion were to slam into the market you would need to buy about 32 million bitcoins to satisfy the demand at current prices, which is of course impossible. Even if half of all bitcoins in existence were to turn over to new owners they would have to sell for an AVERAGE of $3000 per coin, which means of course that the peak price would be considerably higher. And that's only if half of the whole supply were up for grabs.