I don't think you really watch the rams games do you? Austin has gotten many touchdowns and big plays called back due to no fault of his own. The kid got a lot of hype he didn't really deserve but he's playing well and the stats would reflect that if he was on a more disciplined team.
I actually have watched plenty of games and Austin is not even remotely close to living up to his draft slot. He has been outplayed by Chris givens and I would say that Quick is a better receiving option than he is at his moment in time. Aside from one game with 138 yards, his second best game was a 2 td performance against Atlanta where he caught 6 passes on 12 targets for 47 yards in a loss. He had a game where he had that long rushing TD but aside from that he has 39 total yards that game. That's about it.
Will he be good one day? Absolutely. Is he good now and is he producing based on where he was drafted? It's a loud NO.