The JFK assassination happened for reasons similar to the sinking of the Titanic: it was a perfect storm of individuals and organizations on their own making independent and often bad decisions. All of these bad decisions and bad communications culminated in a horrific tragedy. It’s not any more complicated than that.
John Hinckley almost killed Reagan, that was not a conspiracy.
Squeaky Fromm came close to killing Gerald Ford, that was not a conspiracy.
Just because a nut job attempts/succeeds at assassinating a president doesn’t mean there is a large over arching conspiracy involved.
But when you have a trained cia and fbi asset .. and a clear cover up...it fuels the fire.
Perhaps the cover up was simply about keeping that info quiet. They did such a good job you just saw a poster on this thread not believe it because he had not read the file.
Trump got the info out. He could have continued the cover up.