Hi Lucid,
this is an ooooolllllddddd thread. That means it is likely that the main topic (collaboration resp. qualified developers) has been clarified and the participants are probably not listening anymore. Your problem is rather centered about a different topic (judgement, better model) and is worth a new thread.

"The better model" is not the model of higher quality,

You miss a point, a "better model" is rather a model that provides a superior user experience to ~400 million users. That is something Google cares about and in addition to efficiency, a main weight is put on "realism". Realism is not acchieved by modeling many geometric details (window frames) but by using photo textures (as required in the acceptance criteria) and textures of a high level of realism. In addition, the modeling rules explicitely propose to use the satellite image on the roof.

 but that of I suppose an automated process to determine speed and efficiency,...

Models are judged manually and in the (branched) pipeline from upload to release, a model goes through more than a couple of judgements and testings. I doubt any other company would build up a so complex process to value user contributed content.

I'm not sure a "Good Modeler" could ever compete with a "Super Modeler"