Taxes were not the main contributory factor. "Ireland continued to export large quantities of food, primarily to Great Britain, during the blight. In cases such as livestock and butter, research suggests that exports may have actually increased during the Potato Famine. In 1847 alone, records indicate that commodities such as peas, beans, rabbits, fish and honey continued to be exported from Ireland, even as the Great Hunger ravaged the countryside." https://www.history.com/topics/immigration/irish-potato-fami...