History is extremely important. It can help us make predictions about the future and understand circumstances in the past.
This specific incident has been researched to death. There is very little we will be able to understand about the sociopolitics of the past that we don't already know if the hand on the trigger changes. Every hypothetical scenario has been gamed to exhaustion, and which one reflects the reality we happen to be living in isn't going to change modern sociopolitics very much. What would change in a relationship with Russia if we found out a USSR plot killed Kennedy? The USSR is gone. What would change in people's trust in the FBI if we found out they killed Kennedy? That institution's reputation is already tarnished, and the people who would have made the decision to have him killed no longer work there. What would it matter if there was a conspiracy of a few people working with Oswald? We already know that it doesn't take more than one actor to kill a President from other assassination attempts.
Similarly, there is little to be gained studying this topic to exhaustion in terms of future predictions. Kennedy was a singular President existing in a singular time. A series of fairly unique circumstances led him to be universally hated and loved at the same time... Immensely popular, but his combination of willingness to challenge entrenched power and brash indifference to consequences made him dozens of enemies who would have had the resources to eliminate him.
Whether he was killed by a secret FBI project or a lone, angry man with firearm training changes none of those facts.