/**
 * Remove bbPress replies from BuddyPress activity args
 *
 * @param array $r Activity args.
 *
 * @return bool
 */
function wb_modify_record_activity_args( $r ) {

	if ( $r['type'] && in_array( $r['type'], array( 'bbp_reply_create', 'bbp_reply_edit' ) ) ) {
		$r = false;
	}

	return $r;
}
add_filter( 'bbp_after_record_activity_parse_args', 'wb_modify_record_activity_args' );