In my personal view, bumping rating by forging it is plain bad. It does not give the actual picture.

If we look on wp repo reviews, there are not so many reviews(I guess, only 1-2% people provide feedback) and even giving 5-10 five star reviews for normal plugin makes a lot of difference.

We do run a business based on WordPress plugins and themes but we do not allow our own people to even rate it on wp.org as it will be unethical business practice.

I personally believe, only the users of the plugin/theme should be able to provide feedback not the authors as reviews are meant for other users.