bench.php

<?php

$customers = [];

for ($count = 1; $count < 100000; $count++) {
    $customers[] = [
        'id' => $count,
        'name' => array_random(['Lorem', 'Ipsum', 'Dolor']),
    ];
}

$runTest = function ($description, $callable) {
    $startTime = microtime(true);
    $startMemory = memory_get_usage();

    $names = $callable();

    $elapsedTime = microtime(true) - $startTime;
    $totalOfMemory = memory_get_usage() - $startMemory;
    echo "$totalOfMemory bytes / $elapsedTime seconds using $description" . PHP_EOL;
};

$runTest('collect()', function () use ($customers) {
    return collect($customers)->pluck('name');
});

$runTest('array_map()', function () use ($customers) {
    return array_map(function ($customer) {
        return $customer['name'];
    }, $customers);
});