Except your argument is directly contradicted by the actual contest. No VN made it past Round 3. MGS3 beat a VN on the way to the finals. Ever17 almost lost 3 times. There are also a decent amount of 'random' people who have played VNs that aren't dedicated fans of the genre, and they often voted in this contest.
Meanwhile, two Shin Megami Tensei games made Round 5. Is anyone complaining about them, and calling their fanbase biased? Of course not.
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Black Turtle did a pretty good job.