The inspired tennis that made him, for me, the very best of best players, is less evident these days. More than that , or perhaps because of it, he no longer seems to have the consistency required to play his best tennis for a whole tournament, or ability to move up a level to quelch the efforts of a determined opponent.
Add to that the fact that there are some quite excellent other players in the mix, on great form, and hungry for the win too, and the equation of his potential to win gets even more complex. And with Djokovic & Nadal rampant, it seems a truly tall order for Federer to lift a GS title again.
Much as I would love to see Federer win another slam, I would be more realistic in hoping that he can stay in the top five & enjoy his competitive tennis a while longer. If for no other reason, than because for me, just seeing his flashes of brilliance is worth watching. It always will be. The winning is a welcome bonus.