Not having a quad would keep him out of the medals.
Nguyen - probably for the mens
I saw Polina Edmunds at Nationals. Her free program was beautiful - light and ethereal. I was surprised she hadn't been in the JGP last year. I don't know about her consistency but I was impressed at Nationals.
Concerning Nathan Chen and Vincent Zhou. At nationals, Nathan was sick. He said afterward that he had overcome the injury and had been training well. Even had his 3axel back. He was very disappointed in his performance. Aratunian said that he was trying to get Nathan to not be quite such a workaholic. Aratunian thought that Nathan's problems came from his overworking the beginning of the season and not being able to manage his energy throughout the year.
As for Zhou - he has some growing to do as well. Who knows what challenges he will face. Only time will tell for both Chen and Zhou. In 2018 we may see both of them on the Olympic Team - or neither.
I wouldn't be counting out Nam Nguyen from Canada....sure he's a tad inconsistent but remember he's young and I really think he could come into his own this season (plus now he's had a full season under Orser)