How is Boba Network achieving the lowest of all Layer 2 fees?

I just saw on l2fees.info now that they are at the top of the ranking, beating even Loopring which is a specialized, not general purpose scaling solution. Boba fully supports the EVM and I don't see much mention about it, how are they getting these 5 cent transaction fees and 40 cent swap fees?

Is this just a matter of tweaked parameters and lower usage in comparison to Arbitrum and Optimism?