I'm no QB coach so I don't know what is typical, but it always seems that Fitz is reading from the outside in, and we just don't have the talent at WR to look for those routes first. I'm not sure that Aries clears before Fitz is getting sacked, but a little chip from 81 before he goes out on his route gives the tackle time to recover standing flatfooted as the play goes off.
While none of the receivers look open with the exception of Williams, if 81 chips and the tackle regains position it also opens up a hole the size of a double wide for Fitz to take off right up the middle.