I think you guys underestimate how popular and well liked Shinji actually is as a character. The majority of the people that have watched NGE think of it as a classic and regard Shinji as one of the best child characters written. Shinji breaks the mold of generic hero paths of do the thing, get confident, do the thing again, fuck up doing the thing, make a strong comeback, do the thing, save the day, win the girl.
You guys are in the minority of you didn't like Shinji. He's one of the most endearing characters for a generation of people that had similar dysfunctional social behaviors. Even I connected with the kid when he was struggling to get through the day. 'Cause frankly, life is like that a lot of the times. You can't just decide to "man up" and have things go better. It never works out that way, and people relate to characters that are going through the same.