I work in this industry, and they do not do their best. The Blockchain Transparency Institute lists OKex as only 11% real volume[0] yet it is the 6th biggest exchange[1]. Repeat for many other exchanges. Simply put, they need to remove most of the exchanges.

[0] https://www.blockchaintransparency.org/

[1] https://coinmarketcap.com/rankings/exchanges/