Decrease file size upload in Media

By default, I have a 2m limit of uploads. I want to decrease this number. I found out that this code:

function custom_file_max_upload_size( $file ) {
    $size = $file['size'];
    if ( $size > 1000 * 1024 ) { 
           $file['error'] = __( 'ERROR: you cannot upload files larger than 1M', 'textdomain' ); 

    }
    return $file;
}
add_filter ( 'wp_handle_upload_prefilter', 'custom_file_max_upload_size', 10, 1 );

works by adding to functions. However, it does not update the upload size information when the user is on upload screen. It still displays Maximum upload file size: 2MB. How can I change that text to 1mb? Or alternatively, a different approach to decrease the file size (that does not include editing php.ini or htaccess…)

That number is taken from wp_max_upload_size(), and there is a filter: 'upload_size_limit'. See wp-admin/includes/template.php.

So this should work (not tested):

add_filter( 'upload_size_limit', 'wpse_70754_change_upload_size' );

function wpse_70754_change_upload_size()
{
    return 1000 * 1024;
}