Stop complaining about Ahri
Just because Ahri has a high win ratio plus high pick ratio and it doesn't mean that Ahri is op. Ahri is exciting to play and she is popular because her kit is really well made.
Is Ahri op? No, if you lose against Ahri, then you need to learn how to play against Ahri. If you think she's op, then play her
Ahri's Q costs a lot of mana and spamming it results her running out of mana plus she has quite low range abilities. Yes, her movement speed bonus is really annoying but she can't spam it.
Ahri's Ultimate is her only solution to escape, if she gets ganked then she's forced to use her ultimate. This lowers her damage drastically and makes her very vulnerable to ganks and trading in lane.
Stop complaining about Ahri and learn how to play against her.