It looks like this service is intended to replace the kind of random "notify us of a missing manhole cover" type forms that are found in their thousands on gove

It looks like this service is intended to replace the kind of random "notify us of a missing manhole cover" type forms that are found in their thousands on government websites. For those types of applications, emailing the form to a relevant mailbox is probably the correct thing to do, and in many cases it's the way the existing forms already work. Only a small fraction of government services will have their own custom backend application supporting them.