The difference between then and now is the CO2 measurements were science, and the current alarmist dogma and memes are part of the global warming agenda that has gone well beyond the bounds of science.
The CO2 measurements and the fossil burning attribution are still accepted science and have not been overturned or questioned in any substantial way. NOAA has picked up the facility at Mauna Loa but the measurements there remain the same accepted science being performed since the 50's. The remaining questions are mainly around attributing some amounts of the rise to changes in vegetation (e.g. burning the rain forests)
Government science as “accepted science” is a problem.
Not to mention, the last eruption at Mauna Loa before the 1984 one was in 1950.