Unlike drugs which have limited substitutes (alcohol and caffeine I guess), PoW currencies would have several functionally equivalent replacements. I doubt we'd end up ravaging underprivileged communities as they turned to black market Bitcoin.

The USD and the Zimbabwe dollar are functionally equivalent, yet, I'm sure you're not saving in ZD.

You're only proving our point. USD is a reasonable currency for savings and/or as world-wide currency as long as it's liquid, non-volatile, backed by a big, stable and powerful economy. This could change, but not overnight.

BTC's main uses (speculation and laundering) are possible only as long as it can be exchanged into fiat. This can change tomorrow if the right strings are pulled.

If you can't speculate online and in a convenient, legal way, the value of BTC and friends will certainly tank.

Let people trade cryptocurrency to fiat in person all they want, it's completely insignificant.

trading is only a small portion of bitcoin's market cap. most coins are outside of exchanges, in noncustodial cold storage. even without smooth trading platforms people will trade bitcoin peer-to-peer because bitcoin solves real world problems

This is a terrible analogy. Drugs are inherently desirable. There is nothing inherently desirable about crypto coins

You can't have proof of stake drugs. (or other better analogies for really really near substitutes)

It turns out laws do sometimes have effects.