Hey, how about we ignore the issue since I don't particularly care whether money is a "good" or not. But money like all ...things of value... fluctuates in value.
No, they're "printing money" at a relatively smooth pace, which means that people can reasonably predict the rate at which money is going to devalue and judge accordingly while it remains a viable medium of exchange. Additionally, they've been doing it for decades, and although you can't go to the movies for a nickel anymore, we're not throwing dollar bills into furnaces to keep warm either, so clearly it isn't "quickly becoming worthless."