That is the thing, he isn't a #1 right now, but he is being covered like one because he is the only WR that has made plays that the D needs to worry about.....if all of the sudden he is covered by a lesser DB, he will likely be able to produce more.
While the WRs have been far from good, there are alot of issues on the O that contribute to that, primarily a terrible OL that can't let WR patterns develop, a rookie QB, rookie (for the most part) OC, a questionable at best running game, and yes WRs have have had drop issues and from a layman's eye look like they aren't always in the right place at the right time.
I'm not saying Boutte is going to be a game changer, but at this time he has probably shown more than anyone else that gives some hope for his future.