At least 900,000 bitcoins are associated with illegal activities. This is about $ 10 billion.

• Darknet marketplaces - 585,000 BTC.
• Stolen bitcoins - 204,000 BTC.
• Scam project organizers - 98,000 BTC.
• Other illegal activities 3,000 BTC.

https://markets.chainalysis.com/#risk-illicit-placement

One day, all these bitcoins will somehow hit the market.