Don’t know if it is fully accurate. I have 3 accounts and only use one.
For the first one I made I clicked follow on everyone and then found that I follow too many people and just made a new one.
For the second one I got a 30-day ban and just made a new one.
The third one is what I am currently using.
I am not 66% bot. It just happens.
But they count you as 3 users
The point is that they are telling advertisers that you are not one user, you are three, and basing their advertising fees on you being three different users when you are only one with two accounts you don't use and one account you do use.
But you still only have one set of eyes on ads, not three.
I was on LinkedIn during its early hay days, have over 25,000 connections, and managed groups with over half-a-million members. It made my consulting business successful early on but in later years it became clear that less than 10% of the users were active, really only 1-2% sustained activity. Paid advertising turned into a loss as that became the norm. I suspect very similar of Twitter.
But advertizers are paying as though there were 3 people & you are only one. Now multiply that by a few million.