After thinking about this for a while I think we still should forward error events from the stream object. However, only if there is an event listener as to avoid uncaught errors.

function onStreamError(error) {
  const request = this[kRequest];
  if (request.hasListener('error')) {
    request.emit('error', error);
  }
}

Otherwise we end up with hacks like this:

 const incoming = req.stream || req
 incoming.on('error', errorHandler)