Ghostblade and Maw are getting changed in season 7 and they'll be much worse on him than they are now, I think.
We'll see where he lands in the ADC balance hierarchy after that.
In addition You have to consider that in the competitive environment the ability for Jhin to safely force engagements from extreme range is his ymost valuable asset, and that function of his kit is not nearly as powerful in solo queue. That's also why Ashe is a relevant pick in Competitive but its very rare to see her in solo queue.