Display taxonomy with a maximum number of letters

Use PHP to limit the strings, just as in the example you mention. However, we can just build the terms list ourselves, so we don’t have to write any filter. We use “get_the_terms” instead, which returns an array of strings, that we can then output and shorten:

<?php
$max = 30; //define your max characters here    
$terms = get_the_terms( get_the_ID(), 'Artistas' );

if ( $terms && ! is_wp_error( $terms ) ) : 
  echo '<div class="artista">';
  foreach ( $terms as $term ) {
    $term_name = $term->name;
    if( strlen( $term_name ) > $max ) {
      $term_name = substr( $term_name, 0, $max ). " &hellip;";
    }
    echo '<a href="'.get_term_link( $term->slug, 'Artistas' ).'" title="'.$term->name.'">'.$term_name.'</a>';
  }
  echo '</div>';
endif;
?>

That should output a list of links wrapped inside your div (if I didn’t make any typo 😉
Note that the “&hellip” thing is whatever you want to put behind a cut string, in this case it’s 3 dots.

Cheers.