Earlier quoted context omitted.
If the US properly got rid of pennies (instead of Trump just doing another end-run around congress, by ordering the Mint to stop making them, on shaky legal ground), the legislation could easily supersede those state laws.
I think this is wrong. As far as I can tell the relevant statute is 31 USC §5112, and it does not require the minting of all authorized coins: “(a) The Secretary of the Treasury *may mint* and issue only the following coins: ... (6) ... a one-cent coin that is 0.75 inch in diameter and weighs 3.11 grams.” (Emphasis mine) There may be another clause somewhere that requires the Treasury to issue all coins, but that see…
I think we should get rid of the penny, but it's Congress's responsibility to do that, and they haven't. I'm opposed to Congress abdicating its power and responsibility like that.