Los de afuera son de palo
(The ones outside are wooden ) •
The expression roughly means that "the ones outside" are not important, you should not care about people that are not involved. It can be used when someone that is not involved in a situation/task gives an opinion that no one asked for, or to encourage someone not to care about negative opinions.
"Extraño a mi ex, pero mis amigas me dicen que no debería llamarlo." "Los de afuera son de palo, llamalo."
"I miss my ex but my friends tell me I should not call him." "The ones outside are wooden, call him."