First, I don't subscribe to any "lowest chance of injury" arguments. This is a violent game, and any player could find himself on the shelf at any time. And though I don't think there is a safer WR either, it's not like Brown's situation remains completely unchanged. It'll be interesting to see how the departure of Todd Haley affects the play calling. There's a very small change that a new play caller will affect Brown much, but to ignore it completely is a mistake.
Regarding taking Brown over the stud RBs, I don't think there is a right answer to this question. Instead, ask yourself how your decision shapes the rest of your draft. If you take Antonio Brown #1 overall, then, using these ADP stats, your RB1 would then be among the likes of:
Or maybe one of these guys is there (because ADP data at this point isn't going to be indicative of how things look in mid-to-late August):
Flip that against drafting Le'Veon or Gurley with that first pick. You then end up with a WR1 among the likes of:
I don't see A.J. Green or Keenan Allen falling the the 2-3 turn, but maybe that could happen in some leagues. You can't count on it though.
Let's talk best case for your Antonio Brown scenario... Would you rather have Antonio Brown and LeSean McCoy or Bell or Gurley and one of Mike Evans or Doug Baldwin? I am more in the Bell/Gurley and Evans/Baldwin camp, as RB feels like it falls off a cliff after the first 10 or 11 guys (around the Dalvin Cook / Devonta Freeman line somewhere).
In general, I usually subscribe to the idea that, if I am taking RB with my first pick, I tend to go WR-WR with my next two unless some excellent RB value is there. So it becomes more like this:
Would you rather Antonio Brown, Jordan Howard, Doug Baldwin -or- Le'Veon Bell, Mike Evans, Doug Baldwin. I am way more comfortable calling Evans/Baldwin my co-WR1s with a stud RB than having Jordan Howard as a RB1 (or any of the other RBs with possible exception of McCoy even though I'm not loving it).
But if you like Antonio Brown enough and can accept how that impacts your RB situation, then go for it.