[lgick]

let vasya = { name: "Вася", age: 25 };
let petya = { name: "Петя", age: 30 };
let masha = { name: "Маша", age: 28 };

let users = [ vasya, petya, masha ]


let names = users.reduce((arr, user) => (arr.push(user.name), arr), [])

alert(names)

работает.