Thing is, people have 'good reason' to want drugs: They feel good, and mostly, people get addicted. Moreover, there is much less of a scale requirement for drugs. It is pretty easy to make money on drugs when 0.1% of all people are using your drugs.
Whereas, a currency used by 0.1% of your friends / neighbors is totally useless.
These reasons make it 1) easier to suppress a currency 2) harder to suppress drugs.
I feel like you’re reasoning is biased, I’ve seen cocaine usage for adults 18-25 reported around 0.8% to 2.0%, and it sustains an illegal industry. I unfortunately have no figures on bitcoin participation and couldn’t find anything decent when searching on mobile, but I imagine it would be a similar niche.
Bitcoin, at the moment, isn't used as a currency. Nor is it very viable as one. Instead, it is a store of value, much like gold.
Using something as a store of value has much less of a scale requirement. You only need a few people that will be willing to exchange your Bitcoin into something else in order for it to work as savings / an investment. Whereas a currency requires multiple places where you buy goods to accept it. Moreover, those places only really have a reason to accept a currency if multiple customers would use that currency.
Whereas, a currency used by 0.1% of your friends / neighbors is totally useless.
These reasons make it 1) easier to suppress a currency 2) harder to suppress drugs.