Thanks @dconnet for clarification, just to understand your phrase correctly: Do you mean the OS windows or the evernote windows version that is unlikely to have a dark theme support? What is still unclear to me: Does Evernote plan to implement a manual theme for windows and when is the expected release date? What does speak against an UWP Evernote release? Its unfortunate that there is no step in the dark theme train for non UWP apps.
I got hope that the next evernote version 6.18 would finally include dark theme for windows, waiting several months for this. As its released now, I am seriously disappointed. After all other platforms already got dark theme, is the credo for windows still "it's ready, when it's ready?" Or can we expect some more details? Evernote web client in combination with a dark theme extension is an alternative, but does not offer the same smooth user experience as the native windows client.