The Cowboys' defense struggled with Ryan at the helm and he was removed from his position as coordinator after just one season with Jason Garrett's side.
"Whatever people suggest, it doesn't make a crap to me because I know I'm a great coach," Ryan told reporters.
"So whatever it is, it is. But I said in Dallas on my way out, there are a couple better coaches than me who have been fired. Not many, but there's a couple."
Ryan faces his former team on Sunday as the Cowboys travel to the Mercedes-Benz Superdome.