They demonstrably decided generics are not needed for Go at release, or for the following 5+ years, I don't know how that could be seen as false. If they had thought generics are required for Go, they wouldn't have released the language before they had them.
What is often claimed instead, and is indeed false, is that they believed generics should not exist in Go. This is a position that many Go proponents take, but the designers of the language never did.
What is often claimed instead, and is indeed false, is that they believed generics should not exist in Go. This is a position that many Go proponents take, but the designers of the language never did.