I find it difficult to be that categorical. What happened today?
1st set: Federer was a break ahead thanks to a string of brilliant plays returning. He lost that lead immediately because he missed to many first serves and Djokovic played a brilliant passing shot. He had a couple set points on the Djokovic serve but both time the serb found great first serves that Federer could not return. Came the tie break, Federer had a bit of lost opportunities blues while Djokovic had the knife firmly between his teeth.
2nd set: Federer struggled mightily behind his 2nd delivery, but still managed to deal with the only break point he faced. Federer had opportunities at 2-2 (not enough 1st serves for Djokovic, but the serb saved a break point by hitting the line in a really and another with a one-two punch) and 5-5 (a very tense and long game where both player had ups and downs - Federer was in a rally on break point but made an uforced error). Through a magical feat of clutchiness he managed to go from 3-6 down to winning 12-10, so you can't even blame Federer for the missed opportunities during the set there.
3rd set: Federer saves a couple break point early, with a serve and volley that milk a passing error from Djokovic and an ace. He then had a break opportunity where he managed to get involved in a rally, but the serb forced Federer into error. The big regret is really on this 3rd game because the swiss lead 40-15, but then Djokovic did 2 great first serve return in a row followed by a difficult drop volley for a winner to get a break point, but a somewhat framed return messed with Federer's timing, missing long a seemingly easy 1-2 punch put-away. And after the rain delay, Federer asked the question at 30-30 on the Djokovic serve with a decent chip & charge, but the serb was up to the task. After that, only 2 points were won against the servers in 5 games.
4th set: Federer loses his serve because Djokovic strings 4 insane returns (3 on first serves). The swiss tries to put pressure on Djokovic in a couple of service games, but the World N?1 found a great passing shot here, a couple great first serve there and after recovering from 0-30 at 4-3, the serb found another string of great returns that won him a 2nd break and the match.
So really, Federer did not do much wrong today. He did not serve as well as he could have. He made significantly more unforced errors when involved in rallies during the final than he did during the rest of the tournament, which probably cost him some additional opportunities, but even if he almost lost in straight sets, he was not that far from winning in straight sets (set points in the first, won the second, break point in the third).
I think Federer's problem today was that it's very difficult for him to go to the net once a rally is engaged, because Djokovic maintains great depth of shot and is very good at producing passing shots, even when under a lot of pressure. In fact, we saw several time Federer attacking, moving slightly up the court and then tracking back when it seemed Djokovic would be on too good a position to attempt a passing shot. Also, in the rallies, it's a bit too easy for Djokovic to play deep shots with a lot of volume to the Federer backhand, knowing that it's very difficult for the swiss, even on grass, to be aggressive on these balls (just the once, Federer produced an insane combination of a short slice down the line followed by a vicious back hand cross court passing shot, but Djokovic can live with that happening once). Even if Federer tries to run around his backhand, anything that is not a winning shot allows the serb to counter into the open court, forcing the swiss to run and defend in his forhand corner, which, if done well enough, will probably mean a forced error or a sliced squash-like shot. Djokovic even managed to do that off backhands down the line from Federer.
Obviously, the more time passes, the less opportunities Federer will have to win a 18th title, but when you see the ease with which he reached the final these two weeks and the type of match Djokovic had to play to win, I really find it difficult to believe he will no longer be in the conversation in a near future, and, as long as he is in the conversation, he has a chance of lifting the trophy.
PS: Hingis and Paes crushed Babos and Peya in the mixed double final (1 and 1). Paes was on fire. It was so ridiculous that by the end even the opponents were laughing in disbelief.