You can list economic reasons all day long, but with currency, you can't lose sight of the fact that it still has to be *carried*. And no matter how you try to switch it 'round, paper money is A LOT easier to manage and carry than metal money, no comparison: much lighter, more compact, etc. It's not really good policy in my book to make decisions ONLY on economic etc grounds, and ignore the practical aspects of daily use. And in any case I think the possibilities for making bills more durable have yet to be exhausted. Tyvek bills maybe?
Living in the Eurozone, I've been dealing with a coin-heavy currency for over ten years, so I am speaking from experience when I say that it's a real PITA. Especially if like me, you try to keep things nice and clutter-free and don't like carrying bags full of junk. So I hope for your sake that they change their mind! It might save some taxpayer money at the collective level, but at the price (no pun intended) of a lot of added hassle at the individual level.
Besides, unless things in the US are a lot different to Europe, there are plenty of areas in government that don't give good value for money and which could do more for less. It's not like the money saved from having to renew the dollar bills as often is going to be what saves the budget or anything 😉