
If the 'most influential American writer' means 'the one most important to the US becoming its own country', then the answer is Thomas Paine. His American Crisis papers buttressed the flagging revolutionary movement and made the common folk actually care. Before Paine's propaganda, the majority of colonists saw themselves as British subjects and the fight for independence was only really supported by the landed gentry.
The American Crisis papers made the common folk care, and without them there likely isn't enough popular support to win the war.
Paine > Jefferson as pertains to the American cause (and Paine > Jefferson as person).
So many of the great discoveries in science were controversial in their time. "On the Origin of Species", expanding universe, microbiology. Do you really want the government deciding what is acceptable? No, we don't. We fought a revolution to have the ability to think for ourselves.
I'm not that worried though. Even if platforms are subjectively regulated by companies or the government, life seems to find a way. There are plenty of other mechanisms to publish scientific breakthroughs.
Just because an anxiety is not actionable by you does not mean that it is not actionable by someone else. And one way you, who lack the means to solve the problem, can motivate people who can to do so is by raising the profile of the problem. Writing about it is a way to do that.
When Thomas Paine wrote of "the summer soldier and the sunshine patriot" in The American Crisis, he didn't have any direct way to stop soldiers from deserting from George Washington's army because the weather was cold and the fighting was rough. All he could do was highlight the problem of desertion and point out the consequences of their actions. Does that mean he shouldn't have written it?
"Those who expect to reap the blessings of freedom must, like men, undergo the fatigue of supporting it." --Thomas Paine: The American Crisis, No. 4,1777
