Should players decide the meta or should Riot?

This is not a rant about any particular champion or any particular game change, but rather about the direction of balancing. That is to say:

Should the meta evolve organically?

Or should Riot decide that say, a champion was meant for a role and thus if that champion goes outside the role they were originally meant for, they should be shut down immediately through patch nerfs, rather than allow players to figure it out? Or that a champion was meant for a certain strength level and if they exceed it (even if they're still around a 50% win rate, even due to the meta shifts other than the champ itself) they're OP?

A perfect example is Ekko:

He had a trash win rate mid. However pros figured that he had alot of utility, mobility and base damage, so played him as a jungle tank. His base stats then get nerfed. Now he is trash everywhere.

How about Hecarim?

In patch 5.21 he was balanced. In 5.22 he had an OP win rate that spiked due to the preseason. In patch 5.23 his win rate dropped 2-3% with absolutely no changes happening to him because players figured out how to counter him and the meta shifted around him. In patch 5.24 he was gutted and is one of the worst junglers and tops in the game.

What about Lulu and Janna?

They were originally supports. They were then taken mid even though this represented a tradeoff of damage for utility. A Lulu or Janna mid will almost never solo carry as hard as a Lux, Xerath, Talon, Fizz or Zed in terms of damage output. Instead they were used as safe farmers who could then help the ADC late game.

Instead of allowing players to figure it out, they were nerfed.

Sure, sometimes things are legitimately OP. However, alot of the times they are just annoying and players can figure out how to counter them if they had time. Instead patches make large changes to champions or even the game every 2-4 weeks which leaves players very little time to react.

The player base is also to blame. Many low elos blame OP champs rather than their own play. While most of the time it is their skill limiting them, if blatant nerfs or buffs are seen in patches that come out quickly, who can blame them for thinking that some champs are legit OP?