Blockchain analyst, Ergo seems to think this is the case.
Could the PlusToken exit scam be the cause of the BTC sell-off? It looks as though 13,000 BTC aquired from the PlusToken Ponzi scheme are being dumped onto the crypto market. This information comes from blockchain analyst Ergo.

He broke this privously in November of last year:
PlusToken was a popular high yield investment (ponzi) scheme operating largely in Asia. Promises ofhigh returns and stake in a “decentralized” ETH token (PLUScoin) drew in deposits of Bitcoin, Ethereum, BCash, Litecoin, RippleCoin, DOGE, and Dash from unsuspecting speculators.
Ergo on the PlusToken scam

He went on to say:
Following the whale’s trail led to thousands of BTC reportedly controlled by the massive scam, PlusToken. Recently, I found some odd whale behavior merging hundreds of Wasabi mix outputs.
Ergo on the PlusToken scam

He also had this to say in on Twitter recently:
~13k in new PlusToken mixer deposits in last 24hrs.
Almost all previous deposit change has entered mixing, confirming my theory.
Distributions still on/off.
Much slower than September and November…
I see this is good news actually. With the Pluscoin exit strategy nearing it’s end we can look forward to the market correcting to the upside going into the Halving. But, only time will tell if this is the case.