Too bad, if Mr.Stork Exchange remove BTC withdrawal, their service would be fine. 
Let's say I had 0.5 BTC, but no one knows if I already have Bitcoin and I posted a genuine application on there, especially if my account have a good trading history and promise to pay high interest rate. I don't think there's no one will want to trade when I offered big return.
What if I use Bitcoin to exchange it for a shitcoin, and I use those shitcoins to buy Bitcoin again?
It should be fine till now, currently the forum only restrict BTC to BTC trade.Second: If somebody posted on the Currency Exchange board and offered to trade your stolen coins for clean coins minus a fee, or linked to a website meant to effect such trades, that would definitely be disallowed due to the prohibition on illegal trades, even before the mixer ban. The service in question here does not use the phrase "stolen coins": they say "dirty coins", which is definitely different and could include some legally-sourced coins. But when I look at all of their marketing materials holistically, it all feels too close to the stolen-coins-trader example. So I'd lean toward banning this particular service even if they didn't meet the mixer definition. "Make your dirty coins clean" is not something that typical no-KYC exchanges advertise.
What about lending? someone can use lending as a loophole to trade same coins.Let's say I had 0.5 BTC, but no one knows if I already have Bitcoin and I posted a genuine application on there, especially if my account have a good trading history and promise to pay high interest rate. I don't think there's no one will want to trade when I offered big return.