Nothing says diversity quite like being forced to play a role
Seriously though, Riot has done nothing but enforce a meta that they want to be played at a certain time. It has always been this way, no matter the case. Take jungling for example, you are unable to buy a junglers item without smite. Unless if somehow, Riot finds it impossible to find balance behind the jungle items, this is a way to enforce the meta and how the game is played. Players don't like being told how to play a game.
Or Lulu for example. When Lulu hit a solo lane, guess who got nerfed? Right, Lulu. Though, uh, they nerfed her . . . support . . . and not . . . her laning . . . regardless, Riot felt like the meta shouldn't be shifted just because of an odd pick in the lane. The problem with Lulu was that she disabled counterplay for a specific class of warriors/tanks and required a different means of counterplay. Lulu is weak against burst damage and range, if she pushes out she WILL die with one of those champions in her lane. This is talking about top lane. Players don't like being told how to play a game.
Or when Janna got her own lane and she was swiftly nerfed into the ground because a certain caster said it was bs, meanwhile several champions could have been picked to make the Janna mid absolutely hell to play. Champions like 
Not to mention, you don't like losing the early game because of a Janna mid? Oh okay! Just put a scaling mid in, you know, strategize! 
Players don't like being told how to play a game.
Or when Sona got absolutely back handed in nerfs because the enemy team failed to respond to a Sona pick, you know, the support that specializes in the early game and has pretty much shit-tier everything after that. Literally this bitch is forced INTO BUILDING AP and then after realizing this fact, Riot instantly nerfs her because she is doing as much damage as a mage in the mid game. Probably because, I don't know, this bitch is designed like a mage? She even has perfect synergy with 
The only thing keeping her from the mid lane is her poor wave clear. Did you know, that when an enemy team picks a champion, you need to respond to that pick? Yes, it is true! 
I fucking dare you to pick a non healer, shield counter to Sona, that or you can complain that Sona is OP and just avoid the problem entirely. Because fuck that champion. Players don't like being told how to play a game.
Or when tank Ekko came about, and the only soluation Riot had to the problem was the usual. Nerf the champion, not the problem. Did you know that Ekko is not the only one that did this build, which is not only effective but incredibly disruptive? Yeah, believe it or not these champions: 
But instead of actually solving the problem, you know, those tank items that not only make you incredibly tanky but also incredibly strong in the AD department? Those same items that have probably some of the best passives/shields in the game? Need a slow? AD and HP 
. Need more HP AND AD AND a shield? 
Don't have good enough wave clear to actually be a top laner? Ahhhhh that's a poor wittle top laner
, here, take more tank and a sweet passive 
What was that? Did you want an auto attack reset HP, More AD plus even more waveclear AOE damage? 
I didn't quite hear you, you said the enemy team is building armor? Wow, how fucking dare they. Quick, buy this 
and shred their armor- while also gaining AD plus even more HP! Oh you aren't building AD? Alright, you can choose from all of these wonderful items that not only make you do damage, but also have a ton of HP! 
And because our balance team has no idea how to balance these items, we just decided FUCK BALANCE. And put CDR on every fucking item possible, you can thank us later Fizz when we end up nerfing you for jumping around as much as the easter bunny after his third crack run. Players don't like being told how to play a game.
Or when drain tanks became a problem suddenly, thus, nerfing the champion was the only solution to the matter in Riots mind. No, in reality, these: 
Because who needs mana management when you can just build tons of damage with HP as Swain, run into the enemy team and just afk, gun down the nearest mall, get a smoothie, eat a hamburger, come back and notice that you've been sitting on the enemy teams fountain getting endless pentakills while in bird mode. But no, Swain is the problem! Not his endless mana pool and everything else that benefits him. Players don't like being told how to play a game.
TL;DR: If somebody can be countered, don't try it 'fix' it for what ever reason. There is a way to fix it in the current meta, if not, something must be broken or the balancing team just doesn't understand what their 'data' has been telling them. Because believe it or not if you can't wave clear, somebody on the enemy team is going to pick somebody who can and take advantage of that. If your champion can't fight or handle Lulu in the top lane, somebody on the enemy team will be having a lot of fun stomping your face in. This post was actually a lot of fun to make LOL
PS. Also, if you want to counter Graves top: 
      Because nothing says fun quite like healing 200 hp every other Q on a 1.5 second CDR. (I think it is lower than that actually. If you make the shot.) Hope this post was entertaining.
and 
mid with their reworks... double standards much?