You can simply use the date_query
parameter on the user registration date:
$args = array (
'role' => 'subscriber',
'date_query' => array(
array(
'after' => '2010-01-13 00:00:00',
'inclusive' => true,
),
),
);
$user_query = new WP_User_Query( $args );
This part of the WP_User_Query
source code, makes it possible:
// Date queries are allowed for the user_registered field.
if ( ! empty( $qv['date_query'] ) && is_array( $qv['date_query'] ) ) {
$date_query = new WP_Date_Query( $qv['date_query'], 'user_registered' );
$this->query_where .= $date_query->get_sql();
}