That depends on Musk’s goals. If his goal is to make money to pay off the massive amount of debt he gained as part of buying twitter, (as the attempted quick roll out of twitter blue would indicate), then yes he probably needs to care about what advertisers think. If he just wanted to leverage his position as one of the richest men in the world to ensure that twitter was a haven for free speech and screw the profitability, then no he wouldn’t need to be guided by advertisers. He probably can’t both want immediate returns on his investment and to quickly rock the boat though.