They are saying that their is no downside, outside of running foul of laws and regulators, for banks to take money without review instead of flagging transactions as suspicious.
Your response is about additional benefits for them taking the money without questions.
They have invested in their tech team which is both infrastructure and expense. How much of the ~$10 billion it's worth is up for debate, but zeroing it's value is absurd.
The Slate Star Codex article fails to make the case that lowering the general regulatory thresholds for medical devices or drugs improves societal outcomes. It makes a compelling, if possibly flawed, case for the EpiPen, but assumes generalizability rather than showing it.
We know the costs of not having something like the FDA. All one has to do is look at the supplements industry and imagine if real drugs were like that.
Also ignored is how the FDA is a major incentive to create something new that both helps with the problem and doesn't generate an unreasonable amount of other ones. If the barriers to market entry are removed, you are putting the informational cost on the consumer. If it's cheaper to fool them than to do the due diligence in development, that's what will be done. And it's pretty clear from the supplement industry that it is cheaper.
Scott Alexander likes to make the future costs of a lack of new medications argument a lot. He has to account for the costs of a lack of new effective medications as well.
Edit 2:
Scott Alexander doesn't try to make the case the FDA is corrupt. He talks about how Mylan uses the court system and lobbies congress. And his point about costs is undercut by a later post he made about coming up with the chairs statistic: http://slatestarcodex.com/2016/08/31/terrorists-vs-chairs-an...
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