I mean its pretty simple... our top two WRs are out/have been out and our interior OL is the worst in the league (maybe slightly better without the aggie).
Stroud is getting pressured so much, and often from the inside (the worst kind) he has become "gun shy." When he has time, many of the receivers can't create separation, so he is throwing low percentage passes or eating sacks. All of that adds up, and equates to him missing some of the opportunities that he should hit (sometimes soul crushingly bad - like last night)
The interior OL can't pass block or run block (which mitigates some use of our current best offensive player in Mixon) and we have a #3 WR trying to be a #1 and a bunch of JAGs.
When Nico returns he will help all facets as he is an actual playmaker at WR, which will equate to more opportunities in the run game, which should help the protection.... and so on.
Green should have been replaced much sooner in the season, and we got hit by bad luck with Diggs and Nico going down.