I show the reason Distributive Conditional Type needs to be used for Union Type in this post.
If generic type T is passed as Union Type like string | number, then array item will be Union Type as below.
If you need to iterate on each type in Union Type, then Distributive Conditional Type (with extends keywod) needs to be used.
To avoid distributive behaviour in Distibutive Conditional Type, surround each side of extends keyword with square brackets.
