I think masklinn is arguing that, if Republican senators truly believed the president should be an elected king with nigh-limitless power, then during Democrat administrations they would have been eager to approve anything the president put forward, as he was the president-king at that time.

Whereas what we saw instead was them blocking everything they could, government shutdowns etc.

Unless "Unitary Executive" means something a good deal more nuanced than the president being king, that is.