How am I supposed to peel Rengar?

I don't have this problem with any assassin besides this one really. How are you supposed to peel him? Other assassins you can see them coming and zone them and if a tank or a support is there they can cc them but rengar he just instantly jumps on you from across the map. His W im pretty sure removes cc so if he does get cced he just uses w to get rid of it. Rengar also builds to block the first ability that touches him. When a rengar is in the game especially when he is fed it almost impossible to keep him off and I get completely zoned from a team fight.

When I play a tank countless times I try to peel for the adc against a rengar but they still get 1 shotted regardless cause of all the cc he ignores. The tank I play most of the time is nunu and my e and my w knock up isn't even enough to stop him. He's an assassin that has abilities to remove cc. That to me seems like allowing ranged champions to passively build armor and magic resist throughout the course of the game. It completely takes away the downsides of being ranged just like how rengar having the ability to remove cc with his w takes away the weakness and counterplay of an assassin. If he just had that would be fine but his w on top of that is far too much negated cc. Should they remove the cc negation from his W?

Edit: Just wanted to add that in solo queue where everybody is not as organized, it really takes away some his counterplay. Having your team search for rengar when he ults isn't always plausible or isn't going to happen cause disorganization as well as having your team "clump together" to make it harder for him to click on the right target. Even if that does work against rengar that shouldn't legitimately be considered counter play because its more of a player difficulty rather than inbuilt counterplay in the game. Kinda like how some skins change visual hit boxes and some abilites can be hard to see like arclight varus's ult. A lot of assassins counters are team play rather than what a singular person can do and rengar just makes it harder and more unlikely to happen in solo queue.