There is no doubt that, with the current injuries, the Bills probably have the worst receiving corps in the league, and one of the worst even with Clay and Matthews.
However, I am not ready to give up on the running game yet, or even the offense as a whole. Look at the opponent yards per play rankings: https://www.teamrankings.com/nfl/stat/opponent-yards-per-play?date=2017-10-09
The Bills have played the #1, 2, 4, and 6 ranked defenses, and the offense looked pretty good against #18. We have games remaining on the schedule against #26, 27, 28, 30, 31, and 32 x 2.