Well – I am not sure if it is that black and white.
Jacob – correct me if I am wrong but OpenRules provides a hook from Decision Models via Decision Tables to automation of decision logic. Is that not code generation out of a model?

And many others are out there do exactly the same using DMN as a starting point to generate automated decisions.

I am not sure if that is a good idea to do so but I think – James – it is to late!
Humans are lazy and they like automation of dull repeatable tasks. Why would we not generate repeatable decisions and expose them as a consumable services?