Jinx patch history:
3 nerfs, 1 near invisible buff, and 1 bug fix since patch 4.1
I don't really see how you can argue this is a team that doesn't care about balance...
Jinx isn't even OP... she just has 2 things putting her in the high win-rate / high pick-rate bracket:
- She suits the meta incredibly well. AOE damage at long-ish range for teamfights in a teamfight meta. An immobile carry in a meta that's turned from assassins that would normally dive and blow her up to control mages that attack from range. A hyper carry in a meta that favors tanks/bruisers.
- Other ADCs have been nerfed too much that she is lacking competition. ADCs are quite weak overall right now. It used to be that an ADC made the plays in bot lane and the support just 'supported' them, kept them safe from ganks and kept them alive in 2v2 duels. Now the support decides who wins bot lane in early trades while the ADC just focuses on farming. You'd struggle to find a mid/top/jungler that couldn't come bot after level 6 at 2/0/0 and easily kill any ADC that's already 4/0/0.
Jinx is at the level ADCs need to be at. There are maybe 4 others there as well (Vayne, Ashe, Sivir, Tristana). The rest could really use some buffs.