No reverse dependencies, old packages for mono, uses abandoned mono.eclass.
Dotnet Project is not willing to take up those packages.
Open bugs: #679440
Removal on 2024-05-20

dev-dotnet/monocalendar
dev-dotnet/ndesk-dbus
dev-dotnet/ndesk-dbus-glib

-- 
Have a great day!

~ Maciej XGQT Barć

https://wiki.gentoo.org/wiki/User:Xgqt
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