The best solution would be to contribute to something that is already running, and not start all over again. But no one controls innovation, and it follows a course of its own.
It is not always the case. Sometimes you need to build from scratch because what's available is not suitable for what you need/wanted. Grin is a great innovation imo, no ICO, no premine, community based development and so on.
But I do agree that sometimes there is no need to make two or more projects with the same protocols, purpose and weakness. In case of Grin, Beam is considered their main competitors afaik. This probably happens because the developers doesn't know each other, or they have different goals in mind, so they want to make their own network.
I personally like this "Yu-Gi-Oh" development, it produces competitive space in cryptocurrency. As long as nobody gets scammed, we should embrace competition and innovation.