"Not invented here" isn't a syndrome
Every solution is different, because it considers different perspectives and assumptions. But people have one gift and it's called uniqueness. The downside with it is that the less we express it, the more we become like everyone else, simply through interacting with our surroundings. But that's also valid for companies, who look more outside than focus on what they are. When they lose their track, they start preaching how fast it is to build "the next big thing" out of the existing small pieces. In a sense, the faster they go, the less innovative they are and the more they simulate innovation.
We need to let go of such thinking and acting. "Invented here" isn't a disadvantage or sunk cost, but a reason to be here and the way to show what we believe in and what makes us unique. There's nothing wrong if that makes us feel better, as long as we stay humble. To survive, we often need to "re-invent" ourselves first, so "invented here" is as certain as change.
By not reusing existing solutions, companies show their real face, not the one through which they are "gaming" the system. If they can succeed, they will inspire others to do the same. Through the quality of the new solutions everyone would benefit.
"Not invented here" isn't a syndrome. It's the way more people should dare to go.