Nadal fans seem to think that everyone who watches him automatically will think he is an exciting player. There has never been much fun or aesthetic appreciation for me to watch him play because he has a just-get-it-in-play serve, hits the ball from well behind the baseline never on the rise, hits the ball with heavy topspin often far from the sidelines depending on the heavy spin to keep the opponent from hurting him, rarely changes angles, uses speed to keep the point neutral for many shots till his opponent coughs up a short ball that he can put away. He is the apotheosis of a defensive player who plays defensive tennis at the highest caliber for me and he is a beast on slow, high-bouncing clay which rewards this style - but not that great on low bouncing, fast surfaces.
Contrast him to Federer and Djokovic who have huge serves with pinpoint accuracy, take up aggressive return and baseline positions, often hit the ball early on the rise with access to more angles, hit closer to the sidelines, change angles more often, flatten out shots more often when needed and are more willing to come to net quicker (Fed throughout his career, Djokovic more so later). I would much rather watch this more offensive brand of tennis even though they are all power baseliners at the end of the day who depend on their superior movement to win them titles. They are more versatile on slow and fast, high and low bouncing surfaces compared to Nadal.
I would rather watch Nadal play than watch paint dry, but I would much rather watch Djokovic or Federer play than Nadal by a huge margin. I even prefer watching an in-form Djokovic over Federer because of his superior breath-taking returns and superior BH. But, also enjoyed Federer’s greater ability to disrupt rhythm with superior slices and so they are almost the same in terms of entertainment for me. I did enjoy Federer and Nadal‘s more gentlemanly behavior on court over Djokovic by far though as Djokovic behaves like a dick and has never been a good role model on court for kids.