True enough. Yourself, for instance. You almost never get facts, math, or details like game mechanics right.
Since the majority of EVE players will in fact have only 1 account (and even further, will have played that account for only a few hours or days before leaving), then for an ‘average’ of 2.6 requires quite a few active players running 5 or more accounts to get that average.
You also missed the fact that same presentation said the average Fanfest 2022 attendee had 8 account (7.9), which is far more indicative of what ‘serious’ players might be doing. For an average of 8, you need quite a few with well over 10. So apparently 10 accounts isn’t that extreme nor even unusual, and is fairly representative of serious players.
It’s amusing that you continue to struggle with numbers and symbols that seem quite beyond your grasp, but something as simple as mathematical averages shouldn’t be too hard even for you to figure out.