That on-chain fee was just a way for some exchanges to munch some more $, even a single next block transaction wouldn't have cost that much, but with batching it would have been even lower. Anyhow, pretty interesting move, can't wait to see a similar move from the two big "spammers", Coinbase and Binance, but in the latter's case I doubt they will do such a thing, they are using the fees as a motivation to have people use their shitty coin.

Segwit is more expensive...lol
Usually withdrawal fees are one of the most expensive services of exchanges. By lowering to zero, they are making a huge incentive for people to create a lightning wallet.
If all of them would o so it would get rid of a lot of coins that are currently used just because of this fee thing, like Doge and Litecoin.
they still have low on-chain withdrawal fees which is about $19.40 or 0.0005 BTC compared to AVERAGE $18.20 or 0.0004691 BTC
It's 0.0005 BTC minimum, the fee is 0.00001 BTC, quite reasonable. Maybe they have changed is recently?