I have tested this item ✅ successfully on 8b0103e

For the test I changed the following code in ...\libraries\vendor\joomla\utilities\src\IpHelper.php

public static function setAllowIpOverrides($newState)
{
    // self::$allowIpOverrides = $newState ? true : false; // original code
    self::$allowIpOverrides = $newState ? false : false; // changed code
}

The test remains successful.
In other words, does the concerned method do what it is supposed to do?

// Make sure we don't allow IP overrides
IpHelper::setAllowIpOverrides(false);

and that will include joomla.org

Understood. I'm happy to hear proposals to fix this issue. We might have to do some kind of configuration where we get the info from that we run behind that proxy setup?

Understood. I'm happy to hear proposals to fix this issue.

Maybe you can do something with this, see:

Its about bypassing the ip restrictions on voting by bypassing it using the mentiond headers.

see: #32866