Seems pretty consistently used in drug trading nowadays.
That said, evasion of governmental restrictions is and always has been a core use case for Bitcoin. While that's not my primary concern I don't see that as a negative.
I do see some mild counter-evidence. There were two very large dark-net markets that were shut down recently, and the price of Bitcoin didn't seem to respond.
I think you're absolutely right, with the caveat that...
Yes, just because people are coming to Bitcoin with this in mind, does not mean that ultimately Bitcoin is successful at that use case.
Graphs like this coin flow graph[1] and the story[2] that goes with it, make claims that Bitcoin users can more successfully evade government restrictions, seem particularly dubious.
Coinbase, a licensed Money Service business, follows Know Your Customer and grows increasingly interested in their customers. I recently had to answer a follow-up survey about how I use Bitcoin and where my income is coming from, in order to withdraw less than $1000.
It would have been pretty easy to lie on this survey (and the questions were particularly non-invasive) but there's not really any doubt in my mind that Bitcoin is a platform where the users can be tracked.
We're running out of examples of major Bitcoin heists that went unsolved.
Bitcoin is absolutely more trackable than cash, and in a lot of cases (although maybe not so much for "tracking users" who are associated with governments, that already likely do have access to databases which the rest of us don't... but for the unprivileged anonymous internet users who are interested in tracking) Bitcoin is significantly more transparent and even more trackable than the banking system.
[1]: http://wizsec.jp/images/theft_flow.svg
[2]: http://blog.wizsec.jp/2017/07/breaking-open-mtgox-1.html
Sure, but let's compare apples to apples and compare the percentage of USD being used daily for buying illegal drugs (and other illegal) products with the percentage of Bitcoin being used daily for the same purpose.