I don't think the person who wrote this understands statistics because they're not playing a game where randomness is a large influence in the game. If you talk to top poker players about their game they're not going to talk to you about individual mistakes, they're going to talk to you about constructing ranges. A top 5% poker player isn't just going to beat a top 10% player in a single game or single hand, they're going to have a higher expected return over a long period of time. THe point is to come up with strategies that are successful against a large range of opponents. So whilst you can look at a single event and identify whether it was effective in that particular situation, what you're optimizing for is to get the best return over time. So to take the Overwatch example - whilst you may constantly see game losing mistakes at that level, you won't see the same people making the same mistakes constantly.
So basically - for an article that constantly talks about "95 percentile" or "99 percentile" or "moving from 10%-ile to 40%-ile". I just don't even comprehend how you can title something "95%-ile isn't that good" and then not make any effort to actually evaluate how you're measuring 95%-ile. Which, given this is an article about how people generally do things very badly for stupid reasons, I think is rather ironic.