I will preempt this thread by saying yes, I am an Ahri main. She is the perfect champion for me. Started playing in Season 5 sometime between Bard and Ekko, but didn't start playing Ahri until last season.
Why are people crying for nerfs now? The only thing I remember about her being changed was her base mana pool which occurred in the Mage update and a nerf in that her E no longer stops dashes. Yes, she was picked in the LCS, but it's because she's safe. Look at the consistent pool of midlaners in LCS: Orianna, Viktor, and now Ahri. What makes her so good is that the other champs who were OP were nerfed. LB nerfed, Ryze nerfed, Jayce nerfed. Right now, Syndra is popular. Ahri happens to do well into Syndra because Ahri is good at dodging skillshots, which her entire kit is based around.
Yes, Ahri is a safe, mobile champ, but is balanced around that. She's always been a safe pick. And there's nothing wrong with having a few champs who can do a lot, but not specialize in any of those tasks.