Once Bitmex started mandatory KYC verification, most of the derivatives trading volumes moved to Bybit as so on
I don't know much about Bitget's KYC requirements, but I believe it's one of the reasons the exchange has grown exponentially.
And yes, people stopped using that site after they made clear that they are going to enforce KYC, as if they had continued to use it, they would need to reveal their past transactions to officials. And many people weren't prepared for that. What people didn't seem to get that this would be new standard in every legit site that followed regulations.
Some of these exchanges without kyc might survive under the radar, but higher the volume is, more pressure they are going to get. Especially when they are been used to launder stolen crypto like bitmex.
Yobit should be top exchange if KYC was major factor, as they still haven't enforced kyc. It never got hacked and has existed for ages now. It's insanely shady, customer support is horrible and it has "criminal operation" written all over it. But somehow they are still running .
But i would say that trust from the whales, fast site with good liquidity, fast orderbooks, no downtime and clear gui and overall trust, are things what are biggest factors in growth.
Volume is a factor that i wouldn't count in, as exchanges have gamed with that even publicly, by creating trading volume competitions. And this is on top of fake volume they create.