If you search at the google about bitcoin for criminals, there is a lot. For example at this link https://www.thesun.co.uk/tech/5092224/criminals-use-bitcoin-for-dark-web-illegal-activity/amp/. So if there is nothing correct regulations, maybe a lot of countries will be block this payment system. And as the effects, price of BTC will be drop soon. So let's start to discuss, what it the right regulations to avoid Bitcoin used as a payment for crime.
Obviously if it is not a rule or there is no body that protects, the consequence is that there are many people who do not want to join, even if they have joined, maybe the others will come out.