If talent/aptitude doesn't exist, companies sure are wasting a lot of money to give prospective employees screening tests to see if they have talent for certain types of jobs.
I've actually read that, although "talent tests" are popular, and people like to think they can spot a talent, they're actually very superficial and misleading. It doesn't mean talent doesn't exist; it's just that those things can't necessarily predict success.
I think the argument about whether or not talent in chess exists is proof in itself. If people have different thought patterns and different ideas, proved by the fact that people are arguing about it, how can one person's thought processes not be more suited to chess than another's? How can anyone say that people all think differently about everything except chess moves?