Because they are both hard counters to immobile adc such as Jhin and Ashe.Kalista would shit on Jhin in laning phase but they wouldnt want that cause then nobody would pick him both in competitive and casual gameplay.
I still have nightmares about corki instabursting someone for 2k damage in half a second, most certainly do not miss it.
then there is kalista who just lols around you while plinking away at you and you might as well just go afk as a melee because you won't catch her.
I think it's mostly because of how problematic their kits are by design. Let's be honest when Kalista was popular she was extremely nasty and corki was too much as well.
I don't think I speak for everyone, and I agree with what you're saying, but I'd rather have a good 
on the enemy team than a good 
any day.
Sincerely, A melee player that wants to have fun
I don't see why Riot would want Jhin and Ashe played over Corki and Kalista. Your conspiracy theory doesn't make a lot of sense, if anything, Kali and Corki are more interesting to watch
with 
everyone on the enemy team is gonna look like a porcupine into a teamfight... not a pretty fight especially trying to land a skill shot on her while she keeps bunny hoping all over the damn place
Good
Jhin was originally picked as a counter to Kalista in competitive (see: IEM Katowice with Fnatic) before he became so strong that he could be picked into anything. So "Kalista would shit on Jhin" is just bullshit.
