I will never believe that Peter Angelos will permit Manny Machado to play for the Boston Red Sox this year. That being said, I don't think the Yankees as currently constructed are any better than the Boston Red Sox. Both project to be 90+ win teams. The rest of the ALE is substantially weaker.
Arguably the Bombers may be better constructed once the playoffs begin but given the age and the past injury record of some their key players I just can't see them having a cake walk to the ALE title.
Don't be blinded by the Yankees signing of Stanton. They gave up Castro to get him. While Stanton may be a far better player than Castro, the latter's spark, defense and 16 home runs will be missed in the infield by the Bombers. As currently constructed the Yankees have defensive issues. In my view they need Machado probably as much as Boston, but neither will get him.