[raxxorrax]

I actually did read about it. Wikipedia alone can enlighten you about respective controversies. I think critical voices sound more reasonable but it is an open question at least. It is still my opinion as stated.

Show me the produce, some say it is liquidity, and I withdraw my criticism.

[logicchains]

I don't see any controversies mentioned on https://en.wikipedia.org/wiki/Market_maker. https://en.wikipedia.org/wiki/High-frequency_trading mentions some controversies about high-frequency trading in general, but none specifically about market making.