When we discussed the removal of the Classic theme in a previous update, someone from support mentioned that it would be completely removed at the beginning of the new year as part of unifying the UI across all Autodesk products.
If you are making such fundamental changes, it is important that someone in your development team with a real sense for visual UI design evaluates the result — not only from a technical perspective. The current themes look like they were created by someone without a feeling for professional UI aesthetics.
We run Fusion on FHD laptops, 3K OLED displays, and standard 3K monitors. On none of these does Fusion look good now. The Data Panel is overly high-contrast, menus on 3K displays use tiny hairline fonts, and the overall color balance is tiring for the eyes. All of this was reasonably well tuned in the Classic theme.
If Autodesk does not want to bring back the Classic theme, there is a very simple alternative: add basic UI color and font settings to Preferences — as implemented in CREO and other professional applications.
I have been paying for several Fusion licenses for about 5 years now, and the price keeps increasing (which I don’t mind — it’s good software). What I do mind is being forced into unfinished UI changes without any option of choice.