[kazinator]

In this case, I don't see how they help.

A modern language could automatically throw an exception if the string cannot be completely written to standard output.

But that has not necessarily helped. The program now has a surprising hidden behavior; it has a way of terminating with a failed status that is not immediately obvious.

If it is used in a script, that could bite someone.

In Unix, there is such an exception mechanism for disconnected pipes: the SIGPIPE error. That can be a nuisance and gets disabled in some programs.