I hate this new iteration of Rengar. Am I justified?

I haven't played League long enough to play with or against him before his reworked state, until they partially reverted / reworked him recently. For context I am a low elo jungle and support main. (Mainly a 1-trick Nidalee main and a mage or ecnhanter support main, and occasionally play the other roles.)

If I get an early lead or snowball as Nidalee, I still need to take care when playing because I can't facetank and I still die very quickly/get obliterated if I misplay and I still need to land a skillshot to mark them to get off most of my damage and get a big gap closer. I don't play Rengar, yet if feels as if all he needs to do if he gets an early lead is autoattack me or whatever he does. It's like if he gets an early kill the game might as well be over because he can put so much pressure on all the lanes and single-handedly win each lane and jungle while still in the laning phase with his disgusting damage while ganking.

I understand that his assassination potential should be higher than Nidalee's because she also has power elsewhere, but his risk vs reward just feels so awful to vs as a Nidalee main. While I still need to take care with a lead he can just roflstomp and not have to work for anything at that point.

When I play support and he's somehow gotten an early lead, I have to dump my entire kit on him or my ADC instantly. I don't feel like I have to do this with any other jungler. If I interrupt his dash with e.g. a Janna Q Tornado he'll just flash on top of me and still instagib me, if I haven't been able to get tankier stats by that point (then I have to rush like 2 armour items just for Rengar.)

Maybe I'm just crap and have little no idea how his kit works.

Am I justified in thinking this? Or is it simply a case of L2P?