Is this post a JOKE? Seriously? Do people watch tennis? To say the current Nadal is comparable to 2008 - is hilarious at best and BORDERLINE insane at worst.
Forehand: 2008 Nadal by a country mile. His off-forehand (i/o and inside-in) was deadly. Mainly because he was in position and had more explosive footwork. His DTL in 2008 was also far better - 2019 Nadal is usually late and can barely get the ball in. Plus (and more importantly) current Nadal does NOT have the same confidence in his CC forehand. During his prime, even when hitting SHORT, Nadal would hit in the corners. The top spin would then yank his opponent sideways. Now, he puts the ball in the middle of the court and it stands up begging to be hit.
Backhand: Can't even emphasize how much the FLAT DTL backhand of Nadal has gone down. 2008 Rafa had no trouble flattening it out, now he usually loops or spins it back. He also doesn't get in time early enough to hit CC backhand effectively. Push him cross court and he WILL throw a tame slice nowadays. Gets killed by Djokovic (and other top players).
Defense on the forehand: The current Nadal is laughable. All you need to do is hit deep or at an angle to his forehand. All Rafa can do is loop the ball CC. Time was when (in 2008), Nadal was faster and defended his forehand much better.
Defense on backhand: See above. Any person who can hit short CC angled forehands, gets Nadal in trouble. He barely gets to the ball and is totally out of the court. Typically only hits CC back and is super predictable. The 2008 Nadal was faster, covered the ball better and could still hit DTL/middle on the run.
Defense, explosiveness and Movement: No point in even mentioning. Even a blind man can see how much Nadal has declined in speed and defense.
Return of Serve: While Nadal's ROS has never been strong, it has reached a nadir as he has gone past his prime. His reflexes and explosiveness has gone down so much that he suffers on faster surfaces returning serve. Watch how Rafa struggled in Wimbledon from 2012. Compare that to the 2007-2010 Nadal returning on grass. Hell, even the 2017 Nadal got in trouble with Mueller because he couldn't return effectively to save his life.
Serve: 2018/2019 Nadal's serve does not even compare to the 2008-2010-2013 Nadal. The speed, placement, accuracy etc - are all significantly inferior now. This is also borne statistically.
Mental strength: Biggest difference after the movement. The current Nadal is shaky on breakpoints, has a terrible 5th set record, gets broken by everyone and their mother and starts super slow seemingly anxious. Had we not known the mental fortitude of 2008-2013 Nadal, we would never have said Nadal to be a mentally strong player.
In short, there is NOTHING that the current Nadal does better than the prime/peak Nadal. The only thing he has is MORE experience. He is slower, older and the strengths of his game (defense, mental fortitude, transition game etc) are not what they used to be. The fact that he still wins, sometime, is a reflection of the weakness in the ATP tour.