If it was making them money, It wouldn't make sense to remove these coins based on nothing so there must be something that led to this.
According to Binance, they usually de-list due to the lack of:
Commitment of team to project
Level and quality of development activity
Network / smart contract stability
Level of public communication
Responsiveness to our periodic due diligence requests
Evidence of unethical / fraudulent conduct
Contribution to a healthy and sustainable crypto ecosystem
The "making money for Binance through trading volume" factor isn't at least included here, in this list; plus don't forget that there are much more dead coins (by volume) currently listed at Binance if compared with a few of these (CLOAK/SALT/SUB).
Delisting is something good for traders and investors in the long term because, with time and more coins being created, investors will get into confusion and have no idea where to invest and let's face it, 99% of the coins out there has no real use case so a bit of cleaning doesn't hurt and that should also teach people that they should invest based on the technology and the development rather the price and the exchange a coin is being listed on.
Cleaning? It's good when you clean "dirt" and "garbage", and it's really bad when you clean (and throw away) the "gems". Binance just threw a couple of gems, for absolutely no reason(s) at all! There are a number of extremely dead projects with no volume at all currently listed at Binance.
I must say, they are NOT being transparent with their de-listing policy and this will surely hurt them in the future. Look at the style of their support team in this regard:
..."The number one crypto-exchange"...
A couple of months back,
they even gave CLOAK a "V Label".