I think Ruiz enjoyed the World heayweight champion lifestyle a bit too much (as short lived as it was) came in even heavier than the first one (not saying his weight is necessarily a factor) but he looked out of shape in terms of fitness levels and he admitted that himself afterwards.
Some people thought AJ's win was a borefest but to me it was a very professional performance, did what he had to do to win as he knew that Ruiz was a danger puncher, and for me it was a resounding Joshua victory as the scorecards suggested.
Wilder will unfortunately trigger the trilogy clause in the contract, but really we all want to see AJ v Fury and find out who the undisputed champion of the world really is, all the belts, one face, one name.