Let s try to be more visual… Blackrock buys shit ton of btc, decreasing the supply… but doesn t buy anything « on the market » Then the market orders show buyers and sellers, and these orders are not affected by the diminished supply since this supply is the exchange reserve… if the supply / demand had an effect on the « public market » there would be no point to trade over the counter, don t you think?
If OTC is bought up by Blackrock, others will have to start buying on the open market. There's no unlimited OTC supply. If OTC is exhausted, prices spike higher on open market due to exhausted supply.