Also tons of ICOs that are borderline scams flodding the market with Eth when they cashout.

It's basically kickstarter with crypto issue your own worthless tokens which might be used for a future product which might or might no come to any fruition in exchange for Eth, dump the Eth afterwards for cash and profit.

Dark market crashes. Leading to widespread crashes in the cryptocurrency market as well.

Eth has almost no presence on the dark markets.

Even bitcoin is much much more rare than what people would think by reading the news.

What are the primary coin(s) used on dark markets?

Plain old cash, including western union, money gram, gift cards and even PayPal. Bitcoin is used more by "bored" western whales and by the Chinese that need to put their money into something the government can't control than by drug or arms dealers.

What Darkmarkets still use cash, western union, PayPal, etc? My understanding is this all died out once bitcoin became a viable currency.

Then again, I guess I'm mostly just thinking of drug-focused markets, not the other kinds... but still. It'd be bizarre if those kept using the payment methods you mentioned.

Typically Bitcoin-only, but in the past 1-2yrs Monero (XMR) has gained acceptance in certain large venues. I'm not sure, but I suspect your parent commenter may be referring to the large amount of darknet commerce that does not take place using cryptocurrency?

Aren't you forgetting Alphabay being shut down and the founder committing suicide? I am certain lots of people had crypto coins float in Alphabay, which is now just lost. Can't be sold, just lost into the air.

The beauty of the blockchain is that everything is open.

Most of the bitcoins sit in the wallets of rich Americans (or well westerners) and Chinese "investors". The former looks for a cool new investment tool the latter seeks to have global financial influence and a way to get money out of China without ending up in prison for life.

Are you sure the coins in Alphabay are lost? Couldn't the government just sell them off like they did with the coins from Silk Road?

I believe there is a difference between coin seized from the personal accounts and general Alphabay account. Also, this assumes the government has private keys and access.