Thank you for all your responses - this discussion in and of itself is extremely helpful!
@Ryzaadit: I can very much imagine it works like that! What confuses me is that even well-renowned media (actually reporting about OneCoin being a Ponzi-Scheme) pick up the "2nd biggest cryptocurrency by market cap"-narrative - how do they back this up if their so-called "market cap" is fictitious one, and even OneCoins alleged figures are not documented anywhere?
@PrivacyG: Great input! I actually started looking into this right away. So far I only found allegation that they might still be active in Bulgaria in some shape or form - curious to see where that path is gonna lead me!
@DefiDOG91: True that. I actually read a research article dissecting the different types of "Ponzi Schemes" in crypto, and the category of those who seem to have had a legitimate purpose and just "went south" at some point was substantial.
To sum it up, it seems like I'm gonna be searching in vain trying to find any actual "scientifically useful" figures about this scam - but I gather this is due to the nature of their "business case", as you guys have mentioned. It just feels weird trying to put together a scientific thesis dealing with this case, and mostly having to refer to their own bogus data.
I have 2 case studies to analyze and trying to figure out how these Ponzi Schemes could work, despite numerous warning signs. With OneCoin, I can somehow see that at least they did a good job when it comes to their marketing - it seems like they took the Bitcoin success story, then addressed all the "negative" (or potentially worrying) facts concerning crypto (such as risky investment, high volatility, prone to be used in the Darkweb back then, "anonymous" and "dezentralized" which they've been selling as disadvantages, etc.) and sold their "Coin" as a Non-Plus-Ultra having all the revolutionary advantages of Bitcoin while eliminating the bad aspects at the same time. Although I still feel like the red flags were numerous, I can somehow understand how one could've fallen for this very professionally-looking scam.
And then... My second case study is... Bitconnect!! Please don't get me wrong, I don't want to denounce anyone, and I feel so much for all these poor victims having lost their precious savings on this scam... But I did some initial research on this one as well and crawled back in their web archive - their storyline incl. return schemes have been absolutely out of this world, and, combined with a webpage scattered with grammar and spelling mistakes, I ask myself - HOW am I gonna explain why people fell for this???
Long story short - if anyone knows anything about this, or knows someone I could talk to - please let me know :-)