I think part of the problem is that it is very dependent on what the invention is. Yeah, for some nicknack, that's a reasonable time frame. But for some kind of massive project, where distribution, complicated supply chains, and many people are involved, this time gets eaten up quick. Imagine you have an invention, thats totally cool, but 10 years of your time is taken up trying to make it at scale to make it profitable? Meanwhile, someone else can establish all those things without breaking patent, and go to market as your patent closes. You aren't wrong, its just not always so simple.