https://phpstan.org/r/765ef3ab-b796-4421-ae18-21413a869809

class HelloWorld
{
	public function sayHello(SimpleXMLElement $item): void
	{
		foreach ($item->items->children() as $groupItem) {
			switch ((string)$groupItem->orderType) {
			}
		}
	}
}

It produces Cannot access property $orderType on SimpleXMLIterator\|null on php 8 on phpstan.org.
IDK why but this code reports Access to private property $orderType of parent class SimpleXMLElement for me locally w/ phpVersion: 80000 setting enabled.