Talent is a thing. However, it's a bit different from what people think it is: inherent talents are about acquiring skills, not having skills. Talent won't make you magically good at something. What it will do is make it easier for you to practice a skill and let you improve faster. And even then, it only does that if you help it along, and sometimes it's not very obvious how it helps. I have a bit of talent for science and mathematics, but it's not incredibly direct; rather, I tend to start spewing ideas when looking at sciencey things. That doesn't make me magically good at producing good science, but it did help me stay interested early on and it keeps me from plateauing. Talent also isn't necessary. You can get really, really good at something without having any inherent advantage, and lots of people do exactly that.
Talent may be BS, but difference in memory, learning, and concentration are not. So while everyone can improve some people have easier time and higher ceiling.
There are probably many genetic/out-of-your-control-environmental effects which strongly influence your chances of success, but learning, concentration, and memory can also be practiced and improved upon like any other skill.
Not everyone is born with good discipline. Otherwise everyone would be super successful. We all are slaves to our genes and environment, some are born successful some are not.
Extremely advantageous genetics are really hard to measure with current technology outside of fields such as sports. e.g. in strength sports, by the late teens it's really obvious who has it and who doesn't: some can effortlessly pull 3x a weight that's practically unobtainable for someone else of same weight category. Talent is real in sports, there's no reason why it wouldn't be in every other area of life. Talent is optional if you're going to be OK at something, but it's a basic prerequisite if you're going to be competing at world class.
Things are a lot trickier with brains, since there's actually a lot more internal structural variability. Current scanning technology isn't accurate enough to tell us what the teenager (brain structures stop growing by this point) is going to be naturally good at, but that's not that far away given enough investment and the technology and enough data (basically other brains to compare to)
