The wall reinforces and extends the tunnel motif: a design sensitive to it's surroundings is something people often beg architects for in Queen Street developments.
Here's the rendering. The unfortunate cinder block wall was noted by forumers when the rendering came out... looks even crappier in real life. I don't think anyone begs for this on Queen West.
That wall is a mistake. I hope they plan to put some of the maintenance fee money towards graffiti removal because that wall is going to get tagged often.