I think without the darknet markets, the prices of cryptocurrencies wouldn't be where they are right now. For years Bitcoin was used while few knew about it. When Alphabay put up Monero and Zcash and similar onto its marketplaces, boom, the prices rose. Of course these aren't GIANT details, but it's enough to have a decent sized impact on the market. I agree wholeheartedly that BTC has a bad reputation on it though due to it, Mt. Gox, Cryptsy, etc. The only thing we can do? Keep going further and spreading the knowledge as much as we can. People will eventually become more open to it anyways