The dark mode available in One Note was the main reason to cancel my Evernote subscription and switch to One Note. The white screen is causing a lot of fatigue to my eyes and I choose tool with dark themes whenever possible. I am a software developer myself and having a technical debt is not something to be proud of and use as an argument in discussion with your customers. WPF (alternative Windows UI technology) was introduced in 2006 and it is quite easy with this technology to provide themes - i was was used in the application I had been working and and black theme wasn't really a big deal. I have also noticed that One Note provide quite sophisticated font formatting while in Evernote you cannot fix paragraph spacing when you paste text from other sources so I hat to do some crazy acrobatics with Word to format text as I want. This also a long requested Evernote feature which is not yet on the road map yet.
This is a shame that dark theme was not introduced in Windows and is not even planed in the foreseeable future. I am a software developer with some vision impairments and I am having a hard time working with white screens. The most professional application I am working with does support a dark theme or at least supports high-contrast mode. Even Windows enabled dark explorer, what I never believed that will happen. At least I can use Dark Reader in a browser to achieve some prosthesis of dark Evernote.