I feel like you basically rephrased what I said, but added a little terminology around it and said it's a good thing. Market orders taking 1 second to fill instead of 80 milliseconds isn't a meaningful contribution to society.

Imagine a world with no market makers. There would still be plenty of buyers and sellers of SPY shares at any given time to keep a tight spread and fast execution, but people placing market orders would get slightly worse execution and people who can accept the risk of placing a limit order and waiting two seconds would get slighty better execution. The ONLY real difference is that there wouldn't be some market vampires magically extracting tiny bits of profit all day. Your Facebook shares would still move just fine even if nobody front-runs your order and takes a few cents from you.

I get it, market making is profitable and the victims are distributed widely enough/offset enough by trivial benefits that it's not a particularly bad thing to do. But they aren't making ANY positive contribution to society AT ALL by squatting on the exchange and intercepting all the market orders at a profit.

(Full disclosure: this whole argument obviously goes a different direction when you start talking about derivatives, since market makers are mostly the ones who create and offset the derivatives. I could believe an argument that they're making the world a better place by making it quick and cheap to mitigate financial risk)