> given that Robinhood got 40% of their revenue from a shorter

I'm seeing one tweet from Adam Hackney claiming this [1]. Do we have a real source?

[1] https://twitter.com/mindmeld_me/status/1354807424998281217

Yes, Robinhood disclosed that Citadel's MM desk accounted for the largest portion of their payment for order flow income in their rule 606 disclosures. But still a bad take because Citadel stands to make much more money on further trading, and Citadel's hedge fund likely has the capital to outlast retail.

https://cdn.robinhood.com/assets/robinhood/legal/RHS%20SEC%2...

Let me be clear: if I were sales at Robinhood, Citadel MM is a huge client.

But Citadel MM is more likely to pull the plug on making markets in a name for risk reasons than to benefit a hedge fund position. To say nothing of the fact that Citadel got to bail out Melvin Capital, which is traditionally a profitable trade.

I am agreeing with you that there is not much merit to a conspiracy that Citadel asked Robinhood to pull out.

In particular, I believe Citadel would gain more from continued trading on Robinhood than they would lose from their hedge fund positions.

The same shorter is making money hand over fist on market making due to increased volatility, volume, and unsophisticated investors.

Exatcly volatility is the name of the game. They do not care about the direction as long as it moves and if it moves a lot twice as good.

Market makers always win.