Hm, think it sounds a bit fluffy to me. Of course parenting affects children, even if genes are a huge part of it too. You act as your child's role model, they take their lead from you. You teach them how to stick at things; how to be kind and consider others; how to think through problems.... I mean, the list is endless. And that's not even considering diet/sleep etc.
I'm sure everyone knows a family where they consider the parenting to be a problem. The most troubled child I know had some of the worst parenting (IMO:)) . Poor discipline, watching violent films when he was three years old, coke and junk food from 18 months, no sleep routine. No wonder he's a nightmare.
I know that's an extreme, and we put a stupid amount of pressure on ourselves but, tbh, if you know something is best for your child, then I think you have a duty to do it. I don't mean push them into something they hate, but to really KNOW your child, and do what is the right thing for them.