So with all due respect, I beg to differ. The key term I think you did not include was inflation.
When our money system was set up, you could buy a heck of a lot with one dollar - a penny was a reasonable unit of money. Over the years, inflation causes things to cost more. I just looked it up, and a penny in 1776 now is about $0.35 today. Respectively, that means $1 in 1776 was like having $35 today.
So the smallest unit of money today equal the smallest unit of money in 1776 would be about a third of a dollar. Said another way, a quarter today is still worth less than a penny was worth in 1776. So if we were going to "reset" our money to make it work like it did before, we would actually get rid of the penny, the nickel and the dime, and only use quarters and half dollars.
The US mint, with your tax dollars and mine, make the penny at a loss. It costs us a lot of tax dollars to still have the penny and it essentially has no use. Rounding to the nearest 5 cents when using cash rounds up sometimes, and rounds down other times, so it becomes a wash (and, per your statement nobody is talking about always throwing out any money worth less than a 5 dollar bill either...).
So getting rid of the penny is overdue and makes good financial sense.
I would not reset our money. That is the difference.
Inflation just means you can't buy as much with the same money.
It hasn't changed the money, just the amount of things you can trade it for.
Getting rid of pennies does NOTHING to change the value of what a dollar can be traded for. Think about it. If you can buy one banana for a dollar now, not having pennies means what? It is still a banana for a dollar.
The issue is if the banana is not a dollar, but 86 cents. Because it can't be. Not without a penny.
Remember one dollar coins? Of course we all do. Story time:
Vending machine at work sold 16oz bottles of Dr. Pepper for 70 cents. You put a buck in and got your change back.
Dollar coin is introduced. OH WOW SO CONVENIANT!!
2 weeks after they put the new machine in that would accept the dollar coins the Dr. Pepper cost 75 cents. because the machine wouldn't handle nickels anymore. It needed the space for the dollar coins. A month later the machine accepted $5 bills, so it could give you the dollar coins as change. 5 months later the Dr. Pepper cost a dollar. Now there was no change unless you put in a 5 spot.
Do you imagine anyone was happy they didn't have the change anymore?
That is reality for what you suggest. The banana will never be 85 cents. It cost 86 because that's how the math played out. They won't round it down. So now it costs 90 cents. Then in a year it costs a buck. Why? Because the 4 cents of inflation for one banana multiplied by millions of citizens made more inflation.
And then what? Will inflation stop? No, it just grows because no one can raise a price by 2 cents/lb. They have to do it by 5's. Or tens. Then the cycle accelerates.
The only way to avoid this is to make a completely unrelated currency. hey lookie there, the central banks have been buying gold like they know something is up, and they want to make a new CBDC based on gold. How do you think the exchange rate for dollars vs the new CBDC will go? I bet they don't round down for you.
Currency is not broken. The recent rotten series of events is really, REALLY trying hard to make it feel broken so people will accept a new cashless financial system. Don't get sucked into that. That leads to you paying sales tax to your neighbor when you go to his garage sale and buy his old leaf rake for two bucks. And your neighbor required to collect it and report it as income. Because the transaction was digital and went through the FedNow.
Pennies keep all this crap in check, and as I stated are the building blocks of our currency system. The cart isn't broken. leave it be, it will still take the milk to town.