All US hedge funds with greater than $150MM assets under management (AUM) are required to file quarterly statements with the SEC. Among the reporting requirements is liquidity information for each of their positions. Most funds use an assumption that they could absorb up to 10% of the daily trading volume in an asset, and calculate their effective liquidity as the total trading days it would take to sell off their entire position.
Most macro funds are not comfortable with having many illiquid positions, and a fund the size of Bridgewater could not approach anywhere close to a 1% allocation without the position being marked as extremely illiquid.

It's sort of a chicken and egg problem... markets need liquidity to attract big funds, but markets need big funds to have enough liquidity. The strong evidence of rampant manipulation on most BTC exchanges only exacerbates this problem.

Futures markets will help, but the liquidity issues still have to be resolved before we move past cash-settled futures to bitcoin-settled futures. ETF's could help, though the first approved ETFs will most likely trade in cash-settled BTC futures to approximate BTC indexation instead of actually holding bitcoin.

While eventual Wall Street adoption has been at the heart of my HODL thesis since I first started consulting for hedge funds in 2014, we are not very close to that happening, in my opinion.