Christ how stupid can you get.
It doesn't fucking matter if he can get a potentially massive heal or he knows how to kite.
He only has 4 autos, out of which he can't even technically make one full attack a second because one full attack takes longer than one second.
After 4 autos, he is forced to go through a 2.5 second reload he can't avoid or reduce the duration of by any means.
Scenario A, he runs around and gets Warlord's. Cool, he's also 100% health or pretty damn close to it. Charging it takes a long time by the standards of active teamfight (AKA, he's not going to have time to charge it in a split-second life-or-death situation). It's fucking useless.
Scenario B, he has low health and coincidentally has Warlord's and a target at same time. Neat, he gets a chunk of health back. Now what? He doesn't have any more lifesteal. Buying lifesteal on Jhin is a fucking garbage decision because he can't sustain fast enough for it to matter so he can draintank, which is the purpose of lifesteal on the ADC. The only other alternatives being Lifesteal Quints or the mastery. Literally none of his standard builds have lifesteal. And there's a good reason for that. Hooray, you healed back 750 something health. Too bad you're still going to die in a second later anyways after that.
Scenario C, he's low health and doesn't have Warlord's. Well that's just fucking dandy, let's ask the enemy team to not use their gapclosers or CC or burst and just delete me while I try to run around and charge it up.
Scenario D, let's assume the Jhin player is a complete fucking dumbass and buys a Bloodthirster or Death's Dance or what have you. Yay, autoattack once and heal back a bit. Now, let's just ask the enemy team nicely to wait for over an entire full second so I can autoattack again and then heal more. Tell me how that goes, will ya buddy?
It's fucking hilarious how you try to talk down about understanding the game when you are the ignorant donkey, bud.
Jhin's kiting and bonus MS aren't going to do shit against anyone that actually wants him dead and is meant to kill the ADC in the first place.
And for your information, I'm an M6 bordering M7 Jhin onetrick.
Now continue to pull stuff out of your ass because frankly, you're quite an entertaining circus show for me.