Seeing as you only made the post 5 minutes ago, and people are probably only now getting home from school (whether it is do to an extracaricular activity or a college class that runs late) it is no surprise that no one has commented anything, so let me be the first (or 3rd... took me a bit to type all of this).
Jhin has just come out. Like when every new champ comes out no one has absolutely any idea how to play against them. So odds are Jhin got really fed before laning phase ended, and was thus able to destroy everything. Caitlyn on the other hand has been out for a very long time (she was out for free week the first time I played and was the second champion ever that I played). So people know how to play against. My guess is that you weren't as fed. So it is no wonder that Jhin would make caitlyn look second class, but if this wasn't the case then there are other things to take into account.
Jhin I would consider more of an assassin/duelist marksman (with an okay laning phase because his auto range is the same as pretty much every other marksman and he only has 4 shots so extended early trades will go against him) where as caitlyn has the longest range of any adc (aside from tristana who slightly overtakes her late game) she has no reload time, and her abilities are much more efficient for clearing waves and harrassing at the same time (she needs just her q where zhin might need q and w to clear waves with abilities). Transitioning into the late game both still have their own strengths and weaknesses. Caitlyn has insane zone control with her traps giving her insane siege (definitely better than Zhins) and can sit behind her team and right-click the enemy team to death. Zhin has to use his abilities to effectively kite around a team fight trying to get in range (the same range as most other adcs) to use his 4th auto. As far as his siege goes it seems like he has okay poke, but overall you would be better with a corki or ezreal (and caitlyn is definitely better).