What Could Go Wrong?

I think this would have a much simpler effect: killing the money market mutual fund as an investment vehicle.

Money market funds exist solely to provide highly liquid, highly safe returns. If you kill that liquidity, the product dies. I would expect it to be replaced with, for small investors, Money market savings accounts at FDIC/NCUA insured institutions. Or for large investors, exchange traded bond funds.

It's called "financial repression".

I wonder if such a restriction alone would "break the buck" and therefore wipe out the industry.

What, pray tell, does "fair" have to do with the functions of money market funds.

Is this another part of the movement to bring all commercial and financial activity under the "Public Utility" rubric?

Another example of why regulation is about getting the middle class to say "thank you sir, may I have another" while the rich steal the middle's money.

Right. At current interest rates, my mattress will be a perfectly fine substitute for a MMA. And will provide greater financial freedom when I want to take money out, and it's at least as solvent. So where will the next extension of credit come from with rules like this? This kind of reasoning should be called "the Argentina school".

Bank holidays worked so well the first time around, how could they not want to give them another try?