I think he conclude it by analyzing the remaining matches.
I can agree that Liverpool has a higher chance to be the winner because they seem having easier matches.
But Arsenal and Man City look to have the same chance. They still have some big matches, including the match between them (Man City vs Arsenal).
Manchester City are not invincible this year. In some games, they didn't seem so dominant and strong.
Liverpool is in some kind of mild crisis, they have already won a lot of games after the turnaround. Sometimes they showed quality, and sometimes they just had a lot of luck. This cannot last forever. (the last match against United showed just that)
Arsenal is not good when it comes to keeping first place, they showed that last year. We will see if that experience will help them this time.