主要问题是，在 Bootstrap 执行完操作后， active 类实际上最终位于 anchor 元素上，因此您的子选择器找不到它。

在这里，我使用的是 Bootstrap 的 show 方法 ，而不是点击触发器。这更符合 Bootstrap 的设计模式。

$('.btnNext').click(function() {
  const nextTabLinkEl = $('.nav-tabs .active').closest('li').next('li').find('a')[0];
  const nextTab = new bootstrap.Tab(nextTabLinkEl);
  nextTab.show();
});

$('.btnPrevious').click(function() {
  const prevTabLinkEl = $('.nav-tabs .active').closest('li').prev('li').find('a')[0];
  const prevTab = new bootstrap.Tab(prevTabLinkEl);
  prevTab.show();
});

<link href="https://cdn.jsdelivr.net/npm/[email protected]/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-EVSTQN3/azprG1Anm3QDgpJLIm9Nao0Yz1ztcQTwFspd3yD65VohhpuuCOmLASjC" crossorigin="anonymous">

<!-- Nav tabs -->
<ul class="nav nav-tabs">
  <li class="nav-item">
    <a class="nav-link active" data-bs-toggle="tab" href="#home">Home</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" data-bs-toggle="tab" href="#menu1">Menu 1</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" data-bs-toggle="tab" href="#menu2">Menu 2</a>
  </li>
</ul>

<!-- Tab panes -->
<div class="tab-content">
  <div class="tab-pane container active" id="home">
    <h1>Home</h1>
    <a class="btn btn-primary btnNext">Next</a>

  </div>
  <div class="tab-pane container fade" id="menu1">
    <h1>Menu 1</h1>
    <a class="btn btn-primary btnPrevious">Back</a>
    <a class="btn btn-primary btnNext">Next</a>
  </div>
  <div class="tab-pane container fade" id="menu2">
    <h1>Menu 2</h1>
    <a class="btn btn-primary btnPrevious">Back</a>
  </div>
</div>

<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/js/bootstrap.bundle.min.js" integrity="sha384-MrcW6ZMFYlzcLA8Nl+NtUVF0sA7MsXsP1UyJoMp4YLEuNSfAP+JcXn/tWtIaxVXM" crossorigin="anonymous">
</script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.6.0/jquery.min.js" integrity="sha512-894YE6QWD5I59HgZOGReFYm4dnWc1Qt5NtvYSaNcOP+u1T9qYdvdihz0PPSiiqn/+/3e7Jo4EaG7TubfWGUrMQ==" crossorigin="anonymous" referrerpolicy="no-referrer"></script>