The "Mains with a lot of games played on X champion win rate is too high, so nerf" Argument

Before reading this, please know that I've compared win rates between op.gg and champion.gg. Thank you.

Now I see this argument used to justify nerfing and was also used before was nerfed into his current state. However, I've never understood the credibility or strength of this argument. One would expect that if you spent all you're time doing something, eventually you'd get good at it.

I've played Ryze a lot recently and don't see any issues with him outside his W being a tad unhealthy. Other than this, his winrates in past patches up until now suggest to me that people don't want to take the time out to learn him, and he does require good mechanics and timing to play effectively. However, a lot of people want him nerfed due to the whole "people who main him can't be stopped". According to champion.gg, mains nearly reach a 70% average win rate when nearing 125 games played on her. Quinn, Darius, and Poppy all reach around 60% win rates respectively with the same amount of games played, so I don't see why this is a credible reason to nerf a champion. Granted, I have no problem with Ryze's W seeing changes, the best players will adapt and still get results out of him.