Простой вопрос по регуляркам в PHP

Регулярка _не_ такая.

<?php
$pattern = '/^\/products\/([0-9]*)-/';
$text = '/products/1053-vintu-dlja-kompressorov/';
$matches = [];
preg_match($pattern, $text, $matches);

echo $matches[1];

$text = '/products/1053-vintu-dlja-kompressorov/';
preg_match('~/products/(\d+)~si',$text,$m);                     
echo $m[1];