Power Query Functions need strong RETURN DATA TYPES, not un-typed columns

This one has bothered me for a while. Why do Power Query Functions not have a Return Data Type like functions in C# and VB and T-SQL and just about every other coding language?

For example, take the function Text.Combine. It combines multiple columns (which, by the way, must be of type TEXT) but the resulting column is un-typed.

Even Text.From gives you an un-typed column. Really? That's the whole REASON for using that function, is to get, well, TEXT. So why is the return column NOT of type TEXT?