Binance runs 62 pools close to saturation. See AdaPools: https://adapools.org/groups/binance-20. But I am more surprised that every one of them has only 2 ADA in pledge! I am confused why Binance does this since nothing-at-pledge pools are supposed to only earn 77% of fully-pledged pools' rewards. Binance isn't dumb (or so I think) and they have dominated staking for a while, so they should know this better than me. If there's any technical reason behind this, could someone share them so we can better run our own pools? Thank you.
Edit: most Binance pools only have 5 to 10 delegators: https://cexplorer.io/groups/binance though all of them are public pools. In addition, they are promising 15% yields on Cardano so they are probably using a custom system anyway.