This will remove the API key settings from the bbPress profile editor
<?php
/*
 * Plugin Name: Easy Digital Downloads - Remove bbPress API Profile Field
 * Description: This will remove the API key settings from the bbPress profile editor
 * Author: Easy Digital Downloads
 * Author URI: https://easydigitaldownloads.com/
 * Version: 1.0
 */

function pw_edd_remove_bbpress_api_key_setting() {

	remove_action( 'show_user_profile', 'edd_show_user_api_key_field', 10 );
	remove_action( 'edit_user_profile', 'edd_show_user_api_key_field', 10 );
}
add_action( 'plugins_loaded', 'pw_edd_remove_bbpress_api_key_setting' );
To implement this snippet on your site, create a brand new, empty WordPress plugin and paste the above code inside.