Apparently he does not consider "treasury only" money market funds, such as VUSXX, to be safe, nor does he like on-line banks because they might use bait and switch. As a result, he accepts an interest rate that guarantees he will lose out to inflation over the period he intends to hold so he can "simplify." The fear creeping into his thought process is unsettling.
Well - he cuts out a lot of options. I've had accounts at several online savings banks and never experienced a "bait and switch" - although it does sound like the top interest rate banks do pull that stunt and even CIT has apparently changed account types forcing customers to move funds to get better rates.
Also - I would never consider a government type money market fund let alone treasuries only money market to be inferior to any FDIC insured account.
There are more concerns with a Prime Money Market fund. Regulations are much stricter these days, and they have safeguards to slow fund movements during times of crisis to avoid float. So I wouldn't be too worried, but I agree they are not the same as treasuries only or FDIC insured accounts.
It was interesting his concerns reading reviews about Ally Bank. In general they get some of the highest reviews for online banks, and I have never seen any kind of bait and switch stunt. You have to take reviews with a grain of salt and compare bank reviews. You read much worse reviews of other online banks. Ally is super easy to work with online.
Another thing - these banks may go to overseas customer support. But I bet when you talk to their fraud department you are talking to a US team because that's just way too sensitive. That was a very scary story about his savings withdrawal fraud issue, and it didn't sound like it was an online bank where he had the problem.
Looks like at the end he updated his blog to say he'd decided the Vanguard Prime MM fund would be a good option for him.
About simplification - I only moved into CDs and online savings accounts because yields on money market funds had become so abysmal back in 2013 plus the temporary protection for MM funds had expired. Now that things are gradually normalizing, I'll probably eventually go back to perhaps just one high yield savings accounts, drop the credit unions, and use MM funds plus CDs and Treasuries purchased through my brokerage. But I'm in no hurry. With things set up already, it's minimal effort to move funds and super easy to take advantage of things like the recent Ally offer. But I've drawn the line at opening accounts any new CU or bank for bonuses or the latest high yield CD offering.