If you want the trademark to be owned by a neutral body, then by all means create a body to hold the trademark. That's a choice for the project originator (who usually holds the trademark). In this case there's no dispute that Oracle "owns" the trademark.
Leaving aside the legal implications of a trademark for the moment, your hypothesis is flawed at a social level. Who, after all, is "the community". Let's take an imaginary product - which was created by Fred and is now being developed by a "community" of 10 developers. There are say 200 users of the product.
Now 3 of Fred's developers decide to go and work on a fork. Does Fred give them rights to use his product name? What then does he call his product? How do customers differentiate between the two products with the same name? Since anyone can fork at any time, should we have 25 projects with the same name in the same product space?
Ok, 3 seems a little low - what about 6? What if 3 of those developers joined the project in the last month? Does their leaving count as more or less? What about if 9 developers leave?
How best then to determine which is best for the community of users? Who determines which project is "more true" to the original project? what criteria do we use to measure"trueness"? Does the language dictate trueness? Does the location of the original project lead?
In other words, your point is completely moot. Oracle gets to keep the name because they own it. period. (Although it seems they might now be prepared to give it up.) People have the right to fork the code at any time they like, but it's not in our interest to allow them to use the same name. The public is best served, and protected, by changing the name of forked projects. Anything else is just worse.