Only the top 1,5 % should be able to let their voice heard by riot balance's team .
As the lower elos have inexistant knowledge , worthless opinions , bad ideas .
Thats why they are stuck 7 season in a row in the same elo . you shouldn't balance the game around that .
Only the top 1,5 % should be able to let their voice heard by riot balance's team .
You do realize that most of the balance team isn't even in that 1.5%, right? Seems kind-of counterintuitive to have the balance team not listen to itself, nor be able to have an opinion on what can happen. Not to mention lower elo players don't have the mindset of "this is the strongest, so I should be playing this" and are far more likely to get creative.
As the lower elos have inexistant knowledge
Mechanic's and game knowledge are both necessary for climbing. An excess of the first can carry you decently far, but that means that "higher" elo's(statistically, plat is the top 2% of players. Did you know that?) can still have those who are sorely lacking in the second. For instance, take this post on r/SorakaMains discussing statistics for enemies buying executioner's calling against them. One is in diamond, on is in plat, yet for the graph/info sheet that they created, out of 372 games(for the plat guy), only 42 
were bought. For the diamond guy, out of 357 only 16 were bought. Surely for such knowledgeable elos it should be common sense to buy a gw item against a champ who has 3/4 of her kit giving healing?
4.5% and 11.3% buy rates for the counter(during the entire game mind you) say: Apparently not.
worthless opinions
That is an opinion too, just fyi.
Also, surely a main of a champ that is at a slightly lower rank would know better about their champ then a generalist of a different lane at a higher elo, because, as I have mentioned above, that higher elo person is not guaranteed to know a more about the game(they are just guaranteed to be more consistent in their games).
bad ideas
The thing about trends and new strategies, they tend to travel up the ladder. The "low elo", or, by your definition, the 98.5% of the player base(seems kind-of ridiculous when you put it like that, doesn't it?) think about it, try it out, then higher players see and perfect it. Then suddenly it's a new trend. Take Ezreal Jungle. Do you really think that it was created by the top players, who more often than not stick to what they know works? No. More likely is that it was tried out by one person who doesn't have this ideology, then someone else, then someone else... all the way till it caught the attention of one of the "high elo" people and they popularized it.
Thats why they are stuck 7 season in a row in the same elo .
Why on earth do you think that the entire playerbase started in season 1? And that no one had climbed or fell a rank in that entire time. You only need some logic to realize that it makes no sense.
You shouldn't balance the game around that .
Reminder that we just had 2 patches dedicated to pro-play about a month ago.
Also, why shouldn't they balance a game around the vast majority of the players? You seriously think they should not balance the game, even partially, around 98.5% of the players? How does that sound like a good business decision(and yes, Riot is still a business)? Or even a good balance ideology? You are doing something wrong if you are regularly ignoring even 40% of the player base when you make your decisions, let alone 98.5%!
The thing is, the game isn't balanceable across every tier of play at the same time. What's completely broken in Challenger might be barely usable in Bronze, or vice versa. Riot has members from every tier, and they want to cater to every tier of play. The game is very different based on what rank you are.
The game isn't "balanced" at the high ELOs either. The metta is the same 10 champs everytime with the same items. That isn't "Balanced".
This Riot makes games to make money, and the majority of their money is appealing to low ELO players. So they have a voice because money talks.
$$$$
