<?php

$criteres = [
    ['classe' => 0, 'couleur' => 0, 'taille' => 0],
    ['classe' => 0, 'couleur' => 0, 'taille' => 0],
    ['classe' => 2, 'couleur' => 0, 'taille' => 0],
    ['classe' => 3, 'couleur' => 0, 'taille' => 0],
    ['classe' => 1, 'couleur' => 2, 'taille' => 0],
    ['classe' => 3, 'couleur' => 1, 'taille' => 0],
    ['classe' => 3, 'couleur' => 4, 'taille' => 0],
    ['classe' => 3, 'couleur' => 3, 'taille' => 0],
];

$classes = array_column($criteres, 'classe');
$col = count(array_filter($classes)) ? 'taille' : 'couleur';

foreach ($criteres as $critere) {
    echo $critere[$col] . PHP_EOL;
}