I know, I know... But hear me out. Here's a few reasons, in no specific order...
1) Although all of the WR's other than Kupp, Robinson and Jefferson are inexperienced, they do have an abundance of potentially very good WR's currently on the team.
2) If the Rams are serious about trying to bring back OBJ, they would gain back $1.1M of cap space if VJ were traded for a draft pick.
3) One would think that either the Packers or the Vikings would love to add a guy like Jefferson. Packers are very inexperienced at WR and are already frustrating A Rodgers. Van could help that instantly because system is similar. The Vikes would be able to add a guy who pretty much knows the system from day 1 and would replace an aging Adam Thielen. J Jefferson and A Jefferson is a pretty nice start to a WR corps and both are young. Thielen as a #3 for another year or 2 makes for a strong WR corps. If this were to happen, I'd prefer to send Van to the AFC, but honestly the Packers or Vikes seem to make the most sense.
4) Moving VJ allows the rams to get some playing time for a few different young guys and clears a roster spot for a position of greater need. (Are we keeping 3 QB's on the roster this year, again?)
5) If OBJ does come back, there aren't going to be any of the young guys complaining out loud. But, I have to wonder if Jefferson would be pissed about having his playing time cut back, 2 years in a row, if the Rams sign OBJ late in the season again.
6) It's possible that the TE combination of Higbee and Hopkins may account for a few less 11 personnel alignments, and a few more catches this season and that comes at the expense of Jefferson at WR 3. Maybe this makes VJ a bit less of a need for the Rams?
Personally, I really like Van Jefferson and what he brings to the team. He does allow the team to play 11 personnel and leave teams guessing at things when he's in there with Kupp and Robinson. Right now, pretty much anyone else you put in there is going to be looked at as a specialist (speed/deep threat guy, gadget guy, high-point guy, across the middle guy, etc). The one exception may be McCutcheon, but he certainly hasn't proven anything consistently against top-tier talent yet.
I am not promoting a trade. In fact, with 2 knee surgerys in the last several months, on the same knee, he may even be too risky for other teams to trade for. However, should the Rams feel they need to make space in the WR room, VJ makes the most sense to let go of if they can get a 3rd round pick or better in exchange. After Kupp and Robinson, there likely isn't any other WR on the Rams current roster that has any trade value. And, I would think that any of the WR's still left on the Rams roster as of today, will likely get snapped up off of the waiver wire quickly. So, the Rams have to know that the WR's that make the final 53 are the only WR's, currently on the roster, that won't end up elsewhere.
OK... you can crucify me now.