I heard that Capablanca never liked to bother with openings, would never study chess or read books. Despite all this, he became world champion. Is this an exception to the rule? Have times changed today were players are too strong and study is mandatory?
Capablanca didn't like to "study chess or openings" means that he didn't like to study formal chess (as it was understood in his time).
On the other hand, he studied more, and had a better grasp of chess principles, particularly as they related to the middle and end game. His best exposition of this was "Chess Fundamentals."
Because he focused on principles, rather than "book" moves, he was the hardest person in the world to surprise with a new line. He beat back the Marshall Attack that Marshall had reserved especially for him.
Nowadays, there is more and better book knowledge, so it's helpful to learn some of it. And the other reason is that not many players have the instinctive grasp of the game that Capablanca had.
GM Jonathan Rowson recently answered the question "how does anyone get good at chess?" on Twitter in fewer than 280 characters as follows:
Start young (5), fall in love with chess, get lucky with the characters in your particular chess world.
Keep going, be willing to lose a lot, admire someone, study, play, repeat. Befriend computers.
Lose some more. Scream in frustration.
Keep going. Win.
Takes at least a decade
The bad news is that "study" comes about halfway through his list. The good news is that he seems to prioritise other things above study in his list but the first three are things you don't have much control over. They do, though, apply to most if not all of the top players today. Starting early, falling in love with chess and having good mentors / role models in your early development are all key.
I'd just echo the Biblical quote which, although in another context, also applies here:
faith, hope and love. But the greatest of these is love
The point being that when you really love something then studying doesn't feel like studying. It is just more fun doing what you love.
One can have a natural talent for the skills inherent in chess, such as spatial relations and pattern recognition, but without knowing some of the basic principles of chess, most easily obtained through study, it's difficult to see how one could become truly great. Capablanca was supposedly such a natural talent, particularly in endings, but even he found it necessary to study openings when he reached the higher echelons of chess in order to continue to compete successfully. Other natural talents such as Reshevsky found the same to be true.
In those days, people do not have to reckon with tactics and preparation at the level of silicon beings, they just need to play better than the other guy. If Capablanca were still alive today, he would be crushed by most elite players because general principles do not stand up to tactical refutations, especially if they came from the computer.