JSFiddle - React, Tailwind, and code Playground

HTML

<div data-item-type="user" class="js-stream-item stream-item">
<div class="user-content-rest">ccc
    <span class="user-name">aaa
         <span class="protected-icon">ppp</span>
      bbb</span>
</div>ddd
</div>
asdf

<div data-item-type="user" class="js-stream-item stream-item">
<div class="user-content-rest">ccc
    <span class="user-name">aaa
         <span class="protected-icon">ppp</span>
      bbb</span>
</div>ddd
</div>
asdf
<div data-item-type="user" class="js-stream-item stream-item">
<div class="user-content-rest">ccc
    <span class="user-name">aaa
         <span class="protected-icon">ppp</span>
      bbb</span>
</div>ddd
</div>

JavaScript

var p = document.getElementsByClassName('protected-icon');
var cstr = "stream-item"
for (var i=p.length; --i>=0;) {
    var n = p[i];
    while(n.className.split(" ").indexOf(cstr)==-1) {
        n = n.parentNode;
    }
    n.parentNode.removeChild(n);
}