He was ALWAYS a good bruiser. Watch Shy and Dekar playing him in season 3. You guys are probably just newer to the game...
It's just that he was way better and more effective at taking over a game when built with a lot of damage.
We were beginning to see the return of bruiser/tank Rengar right after his last set of nerfs before the rework. Looking at this comment section all I see is salty people who want to emulate a nightblue3 montage and oneshot stuff. Don't mean to be offensive, but that's how you guys come off.
In no way is he less "skillfull" then before. His old Ult gave vision of EVERYONE and you had so much utility and freedom to setup a fight with your team. If anything new Rengar takes more skill. Just go watch ScrubNoob never use empowered W when he should (EleGiggle) and you will see a reflection of yourself not accepting how his new kit works and wanting to just simply dump damage and be done with it.
Only Dekar makes him look really good and actually knows how to play him properly, but he doesn't even seem interested in Rengo at this point sadly.