That means that the power is inversely proportional to the frequency. This is common. You see it in word frequency, river length, population sizes of cities, etc.
So over a 15,000 year period, the biggest solar flare should be about 2x as big as the next biggest. And random Miyake events, which we've had 9 of over roughly 50,000 years, should be about 10x as big as a once every 160 year event like the Carrington event probably was.
All very rough, of course. But it may help give some intuition.
This event is twice as powerful as the previously known largest event, which is at least 10X as powerful as the largest event in recorded human history, back in the 1800s, which set telegraph poles on fire. So, yeah, it's a big Twinkee.
... but the specific strength does come into play when discussing the costs of hardening and mitigation.
This event is twice as powerful as the previously known largest event.