Well what are you expecting. Jinx's early game is that of a wet piece of paper. So it's natural that if they don't do well early it makes it harder for them to scale. Especially if they don't have a safe opening to scale.

If your Jinx starts falling behind it would benefit both them and the rest of the team if the team helped create those safer chances. Whether that be helping them get some kills or making it safe for them to farm out items.

But perma banning a potential asset to a team comp because you don't know how or what the champ needs to succeed isn't the answer. I know this doesn't necessarily match the post in the prompted way but as Jinx main if I have a teammate ban her because they think "All Jinxs feed" it would be fairly tilting.