Has anyone else noticed how parents that are too lineant usually end up with arrogant children?

I'm not saying I believe in smacking children or anything and if parents are too heavy handed and strict it has a negative effect, my mum was used to smack me and my brothers and threaten us with violence and now I don't have much self-confidence or esteem, but on the opposite end of the spectrum you get people who have parents that let them get away with anything. For example my friend's mum is too nice to him and never really tells him off when he acts like an idiot but just tells him hes being a bit silly and just completely bigs him up and tells him everything he does is great. I know as a parent you've probably got to try and build your child's confidence but surely you've got to draw a line or your children will just end up being arrogant as you've always told them they're amazing at everything like my friend, who thinks he's amazing at most stuff, especially football, even though he's not, because their parents are afraid to give them constructive criticism in case they get a bit upset, but in the end it has a negative long-term effect as they just become deluded about their own talents. Does anyone else agree?