If private companies were to sell all the Bitcoin they were holding in their strategic reserves, the market would be greatly affected. In that case, the amount of Bitcoin that Michael Saylor is holding could certainly have a temporary impact on the market. But public companies, especially BlackRock, which basically buy and hold Bitcoin with the public's money, are not private but public and the Bitcoin they are holding is not BlackRock's own.
Since Satoshi is just a fictional character and he has no current presence i.e. no activity so his Bitcoin has not been transferred yet i.e. has not affected the market. If we compare Satoshi and MicroStrategy then I would say that both of them are capable of making a huge impact on the Bitcoin market. There is no room to look down on anyone