So for me, this privacy feature of bitcoin is really taking us off-track than bringing us on-track where we can see organic growth among the legal merchants and users. Really sad to see!
How exactly does it negatively impact adoption though? If merchants and users were such puritans to refuse to use Bitcoin because criminals use, they also wouldn't use cash and some of the biggest banks too. The real problems that stop adoption are giant price volatility, lack of scalability, lack of regulation, complex user experience. Besides, darknet criminals have been switching to Monero for a long time already.