I don't understand why we don't just create a genetically engineered cockroach that wipes them all out by outcompeting and then dying off? The same way they wan

I don't understand why we don't just create a genetically engineered cockroach that wipes them all out by outcompeting and then dying off? The same way they want to with mosquitos. Almost nothing subsists on cockroaches. It wouldn't disrupt the ecosystem at all, especially in cities like NYC.