Since I am not that familiar with AWS and its pricing, I am not sure. Two years ago on this instance, an admin commented on this thread that it cost 180€ per month to run the server. So that's at least 2160€ per year and that's not including the labor and there's only so much volunteer work that anyone is willing to put in, as is evident with the shutdown of lemm.ee, which cited a lack of volunteers as one of the issues that lead to the shut down.