Actually, there isn’t as much difference in the two maps as the author suggests. The NASA map suggests a slightly warmer average temperature, but not dramatically so.
Problem with NOAA data is it does not show SE Australia as being significantly cooler than normal. It was. If you notice over half of the record global warm record readings were in the ocean. So yes if you were a fish it was hot. The error, besides the obvious biases, is taking only surface temps of the Ocean. The Oceans are three dimensional heat sinks. If Ocean current slows, the heat sink is less efficient.