Kogito supports types, but when type errors are made, often this only shows up at runtime. It is quite easy to forget to fill in a type at several points, even in small projects.
IMHO there is loads of value if type errors would be reported during compile time.
As a bonus, type inference could even help more: If the cells in a column all contain a String, but the declaration is something else, an error should be raised (during compiletime, not runtime!) as well.