Class or function. What is better?

play.js

  const stackA = new Stack();
  stackA.push("abc");
  stackA.push("xyz");
  console.log(stackA.stack);
  stackA.stack = [];
  console.log(stackA.stack);

  const stackB = createStack() 
  stackB.push("abc");
  stackB.push("xyz");
  console.log(stackB.stack);
  stackB.stack = [];
  console.log(stackB.stack);
  console.log(stackB.pop());

  const stackC = createStack() 
  console.log(stackC.pop()); 

stack_example.js

class Stack {
    constructor() {
      this.stack = [];
    }
    
    push(el) {
        this.stack.push(el);
    }
    
    pop() {
        return this.stack.pop();
    }
  }
  
  const createStack = function () {
    const stack = [];
    const push = (el) => stack.push(el);
    const pop = () => stack.pop();
    
    return {
        push, pop
    };
  }