How to get a Youtube channel RSS feed after 2015 April 20 (without v3 API)?

After April 20, 2015, YouTube deprecated the RSS feed endpoints in API v2, but channel RSS feeds remain accessible via a direct URL without using the v3 API. You can retrieve a channel's feed by appending the channel ID to the standard endpoint: https://www.youtube.com/feeds/videos.xml?channel_id=CHANNEL_ID

In PHP, you can fetch and parse this feed using built-in XML functions. The following example retrieves the latest video titles and links without requiring an API key or third-party services:

<?php
$channelId = 'UC_x5XG1OV2P6uZZ5FSM9Ttw'; // Replace with your YouTube channel ID
$rssUrl = "https://www.youtube.com/feeds/videos.xml?channel_id={$channelId}";

$xml = simplexml_load_file($rssUrl);
if ($xml === false) {
    die('Failed to load RSS feed. Check the channel ID and network connection.');
}

foreach ($xml->entry as $entry) {
    $title = (string) $entry->title;
    $link = (string) $entry->link['href'];
    echo "Title: {$title}\nLink: {$link}\n";
}
?>

This approach bypasses the v3 API entirely, requires no authentication, and works directly with YouTube's public feed endpoint.