Ok, so his logic says.. people will not take the time to research Tor, but they will take the same time to do research about a new currency or payment method {Bitcoin} also unknown to them?
They know they can create these sites and register them without much hassles, that is why they not making it too complex, and running them in the dark web.
This will become more popular and people will find ways to hide within plain sight.
The thought behind is probably "Why having two hurdles when you can have one?". And we know with certain streaming sites that it is easy to recover. New domain, add a 2 at the end, and you are ready to go by simply duplicating your websites content on that new hosting. Maybe you even don't need to copy, only change the IP where the Domain name points to.