This is a known problem. The initial Debian bug ticket https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=946788 and the corresponding upstream ticket https://github.com/kurtmckee/feedparser/issues/198
Your problem specific to georss is upstream reported here https://github.com/kurtmckee/feedparser/issues/181This is not a "feedparser problem" anymore because feedparser fixed this long ago.
It is a Debian problem because no one upgrade the package even before the Debian 11 release.
