An add-on plugin for the "Simple Website Redirect" plugin that prevents redirects from happening on the homepage.

simple-website-redirect-not-homepage.php

<?php

/**
 * Simple Website Redirect - Not Homepage
 *
 * @package           SimpleWebsiteRedirectNotHomepage
 * @author            Micah Wood
 * @copyright         Copyright 2022 by Micah Wood - All rights reserved.
 * @license           GPL2.0-or-later
 *
 * @wordpress-plugin
 * Plugin Name:       Simple Website Redirect - Not Homepage
 * Plugin URI:        https://gist.github.com/wpscholar/c65523da12007c55962743bbd8eea1d9
 * Description:       An add-on plugin for the "Simple Website Redirect" plugin that prevents redirects from happening on the homepage.
 * Version:           1.0
 * Requires PHP:      5.4
 * Requires at least: 4.0
 * Author:            Micah Wood
 * Author URI:        https://wpscholar.com
 * Text Domain:       simple-website-redirect-not-homepage
 * Domain Path:       /languages
 * License:           GPL V2 or later
 * License URI:       https://www.gnu.org/licenses/gpl-2.0.html
 */

add_filter(
	'simple_website_redirect_should_redirect',
	function ( $should_redirect, wpscholar\Url $url ) {

		if ( $url->path === '/' && $url->query === '' ) {
			$should_redirect = false;
		}

		return $should_redirect;
	},
	10,
	2
);