How does \Magento\ProductVideo\Model\Plugin\Catalog\Product\Gallery\ReadHandler::afterExecute() work?

Context: How does \Magento\Catalog\Model\Product\Gallery\ReadHandler::execute() work?

Details: How does \Magento\ProductVideo\Model\Plugin\Catalog\Product\Gallery\AbstractHandler::getMediaEntriesDataCollection() work?

Details: How does \Magento\ProductVideo\Model\Plugin\Catalog\Product\Gallery\ReadHandler::collectVideoEntriesIds() work?