So...Why does Riot let really high pickrate+high winrate champs thrive?

So, I saw someone make a calculation in another topic that said something like '~52% winrate is the actual average' but that's kind of ridiculous to see considering it's out of 100%. I'd bet that if dumpstered champs were stronger, the avg winrates would fall back to make 51-50% with the same pickrates.

I'm also very sure that a bunch of the midlane winrates have jumped because of nerfs/reworks to assassins.

However, Viktor, Ahri, Orianna, Vayne, Syndra, Caitlyn, Jhin, Jayce, Poppy, Hecarim, Zac, Vi and so on, all have pickrates succeeding at least 7% in plat to challenger ELO, with the mentioned ADCs pickrates each succeeding 25%...and each of them has a winrate of atleast 52%, excluding Jhin at 51.88% at this current time. All pretty much above average winrates if not close to it.

To recap, that means at least 38% of the high ELO playerbase plays 5 mid champs (I think Syndra would be higher if she wasn't banned 37% of the time), almost all% picks between 4 ADCs (with the mentioned 3 having superior winrates), and top/jgl also linger around 15-22% each respectively, each having at least 52% winrate.

Nearly 1/4 of the champ pool for each, and even less for ADC holds pretty much all the highest winrate to pickrate ratios. But since we don't see a lot of these champs in LCS, it's obviously not a problem in these higher ELO statistics. ADC is the only role we'll see about half or less of the roster since ADC pool is small.

Hell, Janna has a ~15% pickrate with a 55% winrate. What in god's name? Why do we let low skill floor champs have such a strong skill ceiling? Arguably, I'd call only Viktor, Ahri, Syndra, Ori, Vayne (before she got buffs to only need 1-3 shots to kill), champs that have a decent skill floor that not everyone can pick up right away.

tl;dr, high winrate champs with high pickrates should be put more into line, imo.

This is just a rant really, I don't expect much colorful discussion out of this since I figure Riot isn't gonna fix the best soloQ/safe picks of the game.