I strongly believe that if some well known investors come in and buy billion dollars worth of bitcoin it could be world breaking news and the price of bitcoin would soar high to $10000, just my opinion.
That could be a factor but do we want investors that are so easy convinced? Because if they can be convinced with such an ease to invest in bitcoin then the opposite holds true as well it will be very easy to convince them to leave bitcoin as soon as somethings happens, so I do not think that is the kind of investors we need in bitcoin.