What!?. Hell no.
Im level 18 and encountered my first Thnderjaw and it was ridiculously difficult. It has a long health pool and Carja Hunter Bow/Carja Precision Bows barely did anything to it.
Ropecaster is also useless against it.
I just didnt know what to do, so I just fled. It either 1-shot me or 2-shot me easily.
That's because precision arrows primarily give you range, they don't really do that much more damage than normal arrows. If you want raw damage you have to use triple shot heavy arrows. And he really is super easy to take down. You are using the wrong arrows and equipment. Ropecaster works on it but you have to use more ropes, unless you have a purple ropecaster in which case you need about 2-3 ropes. The rope down time shortens if you hit an enemy so many that's what's happening with you. Ropes should really be used to give yourself a window of opportunity to lay traps and get a safe distance.
The three easiest way to take him down:
1) 1 tear arrow to disc launcher, it disengages the disc launcher. Pick it up and you can essentially burn him down from full health to zero health just using disc launcher.
2) Bring him down using ropecaster, put fire debuff on...repeat. It's weak to fire and takes massive damage.
3) Set blast and fire traps/tripwires pre engagement. A few of those he'll be down to half health in a second. When he is recovering bring him down again with ropecaster and lay new traps. Repeat.
If you use strategy 1 then you could probably kill him in 20 seconds without even being touched. No matter the difficulty or level.