Restrict and redirect non-members away from the BuddyPress activity or BuddyBoss news feed page.

restrict-buddypress-activity-page.php

<?php
/**
 * Restrict and redirect non-members away from the BuddyPress activity page (news-feed).
 *
 * You can add this recipe to your site by creating a custom plugin
 * or using the Code Snippets plugin available for free in the WordPress repository.
 * Read this companion article for step-by-step directions on either method.
 * https://www.paidmembershipspro.com/create-a-plugin-for-pmpro-customizations/
 */

function my_pmpro_buddypress_activity_page_redirect() {
	if ( defined( 'PMPRO_VERSION' ) && ! pmpro_hasMembershipLevel() && bp_is_active( 'activity' ) && is_page( bp_core_get_directory_page_id( 'activity' ) ) ) {
		global $pmpro_pages;
		$url = ! empty( $pmpro_pages['pmprobp_restricted'] ) ? pmpro_url( 'pmprobp_restricted' ) : pmpro_url( 'levels' );
		wp_safe_redirect( $url );
		exit;
	}
}
add_action( 'template_redirect', 'my_pmpro_buddypress_activity_page_redirect' );