this is not news, I believe that more than 80% of people have already witnessed the strange phenomena of the coinmarketcap volumes, so in my opinion most people already know that coinmarketcap does this. I keep using coinmarketicap to get access to majorities of Bitcoin ANN Thread of the Altcoin for being something that facilitates me a lot
Imho all Coinmarketcap does is take API data from exchanges and remove volume data which is gained through 0fee or other types of incentivized trading. If anyone is faking volume, it's exchanges themselves -
https://chainbulletin.com/blockchain-transparency-institute-report-over-80-of-top-btc-pair-trading-volume-is-fake/