In general, I agree. As for the highlighted part - well, yes and no. He obviously was tired, but even if both Youzhny and Nadal are 100 % on hardcourt, Youzhny wins. Youzhny's problem is that he is very streaky, but when he is on, he is one of the best players on hardcourt. The part that bugs me about the "Nadal was tired" excuse is the implication most fans (not you!) put into it - namely that he would have won, had he been 100 %. The truth is, against Youzhny playing the way he did, Nadal still would have gotten comprehensively beaten. However, he certainly would not have won only 26 % of the points played. So yes, tiredness was a factor, but I believe its importance is greatly overstated by many Nadal fans. The scoreline would have been more competeitive, but the outcome would most likely have been the same anyway.
The bolded part is so true, that is what bothers me about excuses in general.
As for this match, Nadal won easily in the final in Rome after having a long match against Davydenko in the semifinal. Besides, Nadal won easily against Youzhny in Paris when Youzhny had an exhausting match against Haas the previous day. I don't recall Nadal fans saying on that occassion "oh, a piece of good luck for Rafa, Youzhny is normally a bad matchup for him"