I am so glad you mentioned Wikipedia’s discussion of the JFK assassination:
https://www.zerohedge.com/news/2018-05-20/wikipedia-establishment-psyop
I think even Wikipedia sometimes gets at the truth. This is beyond refutation.
Maybe this 1992 Commentary article eviscerating the movie JFK will shed some light on the subject:
https://www.commentarymagazine.com/articles/yes-oswald-alone-killed-kennedy/
At bottom, people will believe what they want to believe. These conspiracy theories are sheer fantasy proving how gullible and credulous most conspiracy theorist are.