Intelligence is a variety of traits including personality, executive functions, moral capacity, and what not. Someone with a higher IQ has an easier time doing calculation, pattern recognition, memorization, and problem solving in chess than someone with a lower IQ, that being said, the amount of work invested in the game is what will dictate for the major part the outcome of the player at hand. This includes the amount of money invested (resource), and amount of time and effort into practising and playing, the way you play (qualitative differences in mindset and also in the way you work), and what not. Chess players with greater insight and greater ability are those invested in the game and they want it to be their life, a principle the applies to not only chess but life as well. A personal note: this can lead to idolatrous living however if people do not prioritize things properly, neglecting the rest of who they are like character, faith/spirituality, and the God-given pleasures of this life (smelling the roses and just laughing).
Another point to contemplate related to the earlier; intelligence plays a role in everything since we are cognitive creatures, but simultaneously well directed hard work pays off no matter what you do. Since intelligence is a broad category, it only makes sense that the categories that are correlated with chess in terms of mental activity are the ones that are relevant when it comes to gameplay and performance. So perhaps you may not be skilled or adept verbally, but you have better abilities when it comes to solving problems or riddles. Conversely, you may lack the problem-solving skills that are found in chess, and to recompense for that you will have to work harder and with more skill. Unless you have an impairment, you should be fine, but even then, the power of faith in God and the drive to succeed can take you a long way.
Rubbish. For a start, moral considerations are nothing whatever to do with intelligence.
I think everybody is smart in their own way. I believe that anybody can be really good at chess if they set their mind to become a very good chess player. All kinds of people play chess.