Do dudes think pierced nipples are hot or should i let it grow back?

Depends: What is "hot" or not is different for every individual. Some would find nipple piercing exotic/erotic while others might find it defiles natural breast beauty. Some might be turned on while others might describe it as mutilation. Similar with other life choices like tattoos, hair color/style, wardrobe, etc. You have to feel comfortable with who you are and what you do.

Your pierced nipple: put you at risk for problems. Nipple piercings can be the gift that keeps giving (pain) because clothing often rubs against them. If they get snagged and pulled out that will really hurt. Infection is also possible. Some men may consider a pierced nipple erotic but many consider it to be unattractive and defiling the body.