JSFiddle - React, Tailwind, and code Playground

HTML

<div id="text">
    <p style="color:red"> paragraph </p>
    <div style="color:red"> div which should be stripped
        <p style="color:red"> paragraph </p></div>
    <strong style="color:red"> strong which should be stripped </strong>
</div>

JavaScript

$("#text *").not("p").each(function() {
    var content = $(this).contents();
    $(this).replaceWith(content);
});