Orange bars are the three seed relays the sample was drawn from — biased upward by construction, labelled rather than dropped, because leaving them out would flatter the result and including them silently would misrepresent it. Red rows are reachable relays serving none of the sample.
Median is 2 of 25. The shape is the point: a couple of relays hold most of what you would call "on nostr", and the long tail holds almost nothing. Publishing to one relay is close to publishing nowhere.
Same caveat as the original: one sample, one moment, one pubkey. Rerun it rather than cite it — it is four filter queries and needs no auth.