Ah, yes, whats talent? A good question indeed, but its pointless to think about it or even fight against others with your oponion.
In my oponion talent does exist and is the sum of various factors, be it things such as genes, personality and other per person things. Therefore you cant accurately measure it, talent got way too much variables, most of which we wouldnt even know they're here.
Its subjective on the person what they view talent as, oponions about have a wide range.
In my oponion talent is the ability to learn a specific skill, on a personal level, this excludes factors such as equipment, further watering down what one can define as talent...
In my oponion the Touhou game "Labyrinth of Touhou" reflexes a good (albeit simplified) idea about talent:
Im taking the extreme example of Patchouli Knowledge, shes very talented in magic power. Now magic power could be any other skill, as example, rythm feel to make it Osu! related.
The screenshot shows the skill upgrade screen which shows us two things, Patchy is already good at magic power, thats because of a mixture of genes, personality, past experiences and so on.
It also shows us that further upgrading her magic power costs only 1 skill point. Thats because shes talented at is, whatever talent might be for you.
She needs less effort to get better in that skill.Now shes bad a physical skills (which could be again any other skill, say... cooking), she starts like this because her past experiences, genes, blablabla, etc etc. Not only that, shes also untalented at it: Upleveling her attack skill takes whopping 7 skillpoints compared to the 1 point for magic power.
She needs to put in more effort to get better at it.However, if she is willing to make all this effort, she can also get good at it, better than some other person who might be talented at this skill. (sorry, id like to put a picture of her having more atk than Remillia Scarlet, which deffinitively is possible, but it takes more effort than im willing to make for this post)
Now both in the game, real life, and osu, you get skillpoints for doing hard work.
When you wont put effort you wont get better, simple as that.
However unlike this game, you dont get to distribute your skillpoints freely in real life and since Osu! depends on your real life skill you wont get to distribute freely for Osu! either.
TL;DR Talented people will always learn the skills faster than those who arent as much talented, but the untalented can make it up by giving it more effort.Edit: See this one person who rises faster in the ranks than you do? Maybe hes more talented than you... Maybe hes not but puts extra effort.