It seems to me the topic has shifted a little.
At first, the point was that bumper cam may be an unfair advantage. Which, given the timing bug that I believe exists, is a fair criticism. I don't believe this bug existed in prior Academys, so that only works for this year. That said, everyone has the opportunity to switch to bumper cam, basically making it a moot point in my eyes.
Now, it appears the topic is more about "realism", which begs the question... should DS3 users then not be allowed to participate? I've never seen a car with an analog stick used for steering.
To me the main point to GT Academy is, is it working? Based on the success of Lucas, Jann, Jordan, Bryan, Wolfgang, etc., I'd say yes, it's working just fine.