The 26-year-old endured a tough training camp session as he threw an interception and missed on several throws, leading to criticism from fans in attendance.
Ryan told reporters: "Our fans have a right to do anything - I'm not going to say I'm disappointed with the fans - but I think we need to move forward. The things in the past are in the past.
"Let's focus on what we have in front of us. We're all going to make mistakes. I had a bad year also last year. Hopefully, our fans are all united 100%."
The Jets begin their pre-season campaign against the Detroit Lions on Friday.