One that comes to mind for me: “Whatever doesn’t kill you makes you stronger” is not always true. Maybe even only half the time! Are there any phrases you tend to hear and shake your head at?
“You can not buy intelligence”
But the product of appearing intelligent is sold: private Education. Also you need to be able to afford the right condition: Not starving to death to appear intelligent, afford food & afford some water without lead contamination (since lead in the water lowers IQ), lead pipes where used for drinking water in poorer areas … Also research and innovation costs lot of upfront capital investment and connections nowadays.