[tome]

The problem with omitting language features like this is that the programmer is then forced to implement them by hand in an error-prone way. It's the same issue with Python and tail call optimization. Guido refuses to implement tail call optimization, so the programmer has to implement it herself in terms of a loop. Go refuses to implement sum types, so programmers code them up by hand. In neither case is the code actually clearer.

Since proper error-checking in Go actually requires doing by hand what a pattern match would have done anyway you're not simplifying anything for anyone by omitting them; you're just making it harder for the compiler to provide compile-time checks.

A pattern match is basically a switch statement. Go already provides the latter so the language would not need to become more complicated.