CZ already confirmed that they are going to acquire CMC after-all. We might see some improvements and removed shit projects being advertise on that platform so I'm expecting a big change when they take over. There could be no API manipulation, they are just pulling the data from every exchange. However, if there is a reported fake volumes on exchanges being shown in CMC then they should do some due diligence to check everything before displaying in their service so that no one will be mislead by it, specially shit projects and scam exchanges.