'Pro: saves X amount of coding hours. Con: may silently return wrong results.' is a terrible philosophy. It's like saying 'well, the surgeon messed up, but at least the surgery was cheap'.
Two points
1) the glue code you HAVE to write to make the composition in other languages and the mantianability issues you get also may introduce wrong results 2) MAY doesn't mean it will and we trade-off speed / convenience and risk in many other areas. Surgeons (or the health system in general) do trade off % of success for cost / speed, just because they don't have the resources to do everything / spend 100 hours on everyone