year
-----

$_GET['filter_year];



$values = ['2022', '2021', '2020'];

foreach($values as $neco) {

 // SMAZEME
 //$link = '?filter_neco='.$neco;

 // NOVE
 $link = sestav_url_film_filtrace($neco, 'filter_year');

 echo '<li>.....</li>';
}
-----

function sestav_url_film_filtrace($value, $type)
{
  // ?nazev=hodnota&nazev2=hodnota2&nazev3=hodnota3
  // ?filter_year=2022&filter_workshop=INT
  // ['filter_year' => 2022, 'filter_workshop' => 'INT']
  $url_get = $_GET;


  $url_get[$type] = $value;


  // https://www.php.net/manual/en/function.http-build-query.php


  return '?'.http_build_query($url_get);
}