You know what, I hate this argument. I really do. It -always- assumes the situation where a Diamond player is wrong but the bronze player is right. It never accounts for the inverse where the Diamond is right and the Bronze is wrong. Being honest, the latter is WAY more common than the former.
More importantly, we need a distinct separation when it comes to balance vs. design. Anyone can have an opinion on design. Hell, some of Riot's designers aren't that good at the game and that's ok. Design is about the mechanics, not the quality of your talent. Comparatively, balance is raw numbers and stats. Only higher-level players/pros can really tell you earnestly about stats because at that level, the numbers matter most of all.
Finally, this sense of "You're bronze so you're wrong' comes from repeated, obvious and CONSTANT backtalk to players of higher levels. Back in the early days of League, great players would go out of their way to explain these things. They still do sometimes. Yet these players were given massive paragraphs of misinformation, bias or just self-serving examples where the gold and below player hides behind the shield of "Well in -my- ELO" or "Well in -my- games". It boils down to high-ranking players being sick of trying to argue with someone who obviously doesn't know what they're talking about and will throw poor example after biased information to justify their inaccurate position. You can't be a brick wall and expect someone to be reasonable with you.
I'm absolutely guilty of this too. I don't want to be but I'm welfare gold. My knowledge on the game from a mechanical standpoint is "ok" at best and my views on design and balance are mediocre at best. However, I absolutely recognize when I'm wrong and don't push the issue. I can talk about balance and design as much as I want but I certainly don't have the experience a diamond+ friend has.
Rank -does- mean something, whether you like it or not. Eat humble pie once in a while and accept that you won't know as much as the Diamond 1 Zed main when it comes to how "broken" Zed is.