It's my personal opinion. I don't generally hold to it myself. My bigger problem is frankly the way that Ebert talks about it. Part of me wonders if he were still alive - and in this era - he might have changed his mind again. He was willing to do so with films that were problematic in other ways - he made a major about face on Triumph of the Will.
On a side note, that fact I noted about the Academy Awards nominated Foreign Films in major categories the year after they won, I only recently noticed something that, as a fellow scholar might interest you as it affected two great directors in two of their earliest masterpieces.
In 1975 Jaws was nominated for Best Picture but Steven Spielberg was passed over for Best Director for Frederico Fellini for Amarcord. (There's actually TV footage of his reaction to it.) In 1976, Taxi Driver was nominated for Best Picture but Martin Scorsese was passed over for Best Director for Ingmar Bergman for Face to Face and Lina Wertmuller for Seven Beauties.
Now I'm not saying that Spielberg would have won in 1975. All five nominees for Best Picture are classics in their own way (Nashville, Dog Day Afternoon, One Flew Over The Cuckoo's Next, and Barry Lyndon) It's a tougher call in 1976 but Rocky, Network and All The President's Men are among the best films I've ever seen. (The bigger robbery is that Sidney Lumet didn't win Best Director for either of those films, if not both.) But in retrospect, this would be part of a pattern that sadly affected Spielberg and Scorsese's careers for the rest of the 20th century. In Spielberg's case, he would either be nominated for blockbusters and lose to lesser films or, until Schnindler's List, direct serious movies and not get nominated. Scorsese was basically ignored altogether. He did almost all of his best work in the twentieth century and received a grand total of three Best Director nominations (and for Last Temptation of Christ, it wasn't nominated for Best Picture so he had no real chance then either.) On a side note I've also felt that Jodie Foster should have won over Beatrice Straight for Network. There's a real argument Straight shouldn't haven't been nominated at all and Foster's work was the best of the field.