This is a great idea. I really do like this.

However, we shouldn't forget the reduced security of the situation. This opens entirely new attack vectors by introducing the otherwise fantastic ability of local programs to consume network input.

With the flexibility and utility of local information comes additional remote attacks. In doing so, this extension blurs the lines between the greater difficulty of remote attacks vs local attacks. Many programs never considered in their threat models that input would come over the network. There are many developers who never try to protect past a certain point, saying, "if the person gets this far, there is nothing we can do anyway", then they ship.