Given that over 750 people have signed the letter, it's safe to assume that their motivations vary. Some might be motivated by the financial aspects, some might be motivated by Sam's leadership (like considering Sam as a friend who needs support). Some might fervently believe that their work is crucial for the advancement of humanity and that any changes would just hinder their progress. And some might have just caved in to peer pressure.
>>kareaa+(OP)
Most are probably motivated by money, some are motivated by stability and some are motivated by their loyalty to sam but i think most are motivated by money and stability.