You talking about "the government" as a unified entity seems odd to me here. The various bank regulators (FDIC, OCC, and yes, that same Federal Reserve) already have access to huge data flows. If they are already misusing it, it doesn't sound like this would be worse. And if they aren't, then I'm not seeing why that lack of misuse would change.
1) Even assuming they get all bank data (which can be assumed, but is uncertain) they don't get access to physical cash data, which might also be phased out in the event of a national digital currency.
2) Nothing about your comment addresses my concern about government power.
I think concern about government power is valid and important. Which is why I think it's vital to save talking about it where there's actually a material difference in government power. I don't think it is here, and you haven't given any reason why it would be.
Off the top of my head, here are some possible concerns and avenues for abuse.
1) Today, the government needs at least the pretense of a warrant or at least legislation to allow them to legally snoop into your financial affairs within a bank. Spying on you would probably be a lot easier for them on some kind of central digital currency that they'd manage. Want to buy a 12 pack of giant buttplugs or a Quran? Uncle Sam is going to know about it in our brave new centralized currency world.
2) Cancel culture and removing classes of people from the economy for wrongthink views, or even just actions that their politicians take on their behalf is already a thing. It's not hard to see a future authoritarian government making financial life for their political opponents hell.
3) Programmable centralized money allows central bankers to have unprecedented control to impose policy that would have been close to impossible to implement before. Keynesian thinkers for example view the idea of money flowing through the economy quickly as one of the big avenues to prosperity. It's not hard to see them clamoring for effectively a tax on money that sits in your wallet too long without being spent to promote consumption, or any number of experiments now that the tool exists to make it possible.