the way the game CLEARLY shows you that Cloud was there experiencing everything firsthand and that he only projected himself into Zack's role as a 1st class SOLDIER instead of a grunt, when retelling what happened. He doesn't act like Zack or recognize anyone from his life ffs...
Because they aren’t. This has never been established anywhere in canon.
Cloud isn’t a Zack clone. Didn’t get a Zack brain transplant. His memories have always been HIS.
This is such a huge part of his character, it’s insane we’re still hearing this BS 30 years later.