JSFiddle - React, Tailwind, and code Playground

HTML

<nav class="adminTabs">
    <ul>
        <li id="adminCloseAll" class="closeAll" style="float: right;">
            <span class="closeAll">Close All</span>
         </li>
    <li id="user157" class="user  active">
            <span class="tabClose">x</span>
            <span class="customer  ">lewis</span></li>
    </ul>
</nav>

JavaScript

$("nav.adminTabs ul").find("li:not(#adminCloseAll)")
    if (true){    
        $("nav.adminTabs ul").remove("li:not(#adminCloseAll)")
    }
    if (false){
        $("nav.adminTabs ul li:not(#adminCloseAll)").remove()
    }