Since previous Whonix in KVM maintainer HulaHoop was last active on January 04, 2015, it’s safe to assume this person got lost. No idea why HulaHoop went inactive. There was no notice of departure, argument or whatsoever. I would like to thank HulaHoop for its work on support for running Whonix inside KVM. As of Whonix 9, the status was “testers-only” and would likely have changed to “stable” in Whonix 10. So most integration work is already done. A new contributor would be welcome to take over from there.
What does this mean for you as a user? No one from the Whonix team will keep KVM in mind. Any eventually upcoming security issues with KVM with respect to Whonix would go unnoticed. Questions in Whonix KVM sub forum will likely not be answered by anyone from the Whonix team. You are encouraged to move on to still supported platforms. The KVM wiki page has been updated accordingly to reflect this information.
Unfortunately, due to work generated by blessing a platform as supported, the current Whonix team cannot takeover HulaHoop’s task. A dedicated maintainer is required for that platform. This is partly because KVM is too support intensive. There are too many KVM’s installation issues from various distribution package sources. KVM’s non-helpful, cryptic error messages if the xml files are using a feature, that is is not available by the platform and because one ought to look over KVM changelogs and to think though if/how those affect Whonix.