Javascript：从数组中删除特定项目并返回没有这些项目的原始数组

JS 新手。做一个练习，我想从数组中删除一些特定的项目，并在没有这些项目的情况下返回原始数组。我以一种方式做到了，但示例解决方案完全不同，我想尝试并理解它。

我的思路是否正确（请参阅下面每行代码后的注释）？我想我明白了，但我不确定我的推理是正确的还是我运气好。我想确保下次我看到这样的事情时我完全理解。

const pull = (arr, ...args) => {
        // In this case, arr = arra1 and ...args = the values "a" and "c"
    let argState = Array.isArray(args[0]) ? args[0] : args;     
        // I think this is saying, "Is the first item (index[0]) in arra1 included in the list of the arguments that follow (in this case, "a" and "c")?"
        // The value of arra1[0] is "a", which is indeed one of the arguments that follow, so the ternary operator would return false and give you the "args", which are "a" and "c" in this case.
        // "a" and "c" form an array (do they? I may be wrong here), so Array.isArray() would evaluate to true, and therefore argState = true
    let pulled = arr.filter((v, i) => !argState.includes(v));
        // I think this is saying, "Loop through arra1. v is the first value, "a" in this case. "Does argState contain the value "a"? 
        // It does, so it will come back true which will evaluate to false when we apply the "!". So "a" is NOT filtered into the new array called "pulled". 
        // Second loop, does argState contain the value "b"? It does not, so it will come back false, which will evaluate to true when we apply the "!". So "b" IS filtered into the new array called "pulled". 
        // And so on and so forth, and we would end up with "pulled = [ b , b ]" for this line.
    arr.length = 0;
        // I believe this just empties the original arr, or arra1 in this case. So arra1 = [ ]
    pulled.forEach(v => arr.push(v));
        // Now we loop through "pulled" and push each value onto arra1
    return pulled;
        // This will return the original arra1 with the new values [ b, b ]
  };

let arra1 = ['a', 'b', 'c', 'a', 'b', 'c'];
console.log(pull(arra1, 'a', 'c')); // will return ["b","b"]

我的主要困惑源于!argState.includes(v)部分。如果argState在我们前行结束了的值true或者false，它没有任何意义，我认为我们可以检查是否argState包括值(v)从arra1阵列（即“A”，“B”，或者在这个练习中的“C”） . argState当它已经设置为值true或false因为 Array.IsArray() 检查时，如何包含这样的值？