When I first used the Dark Theme, I too was dismayed.
I tried the Grey Theme on older versions and found it all looked mushy and less professional.
I persevered and because I use Shortcuts equally with mouse actions I found the new colour scheme less intrusive.

The top toolbar does not have a hover effect compared with the sidebar, which definitely is poor UI design. Pop-ups are not the same and intrusive.
We should have a Context toolbar and not just rely on right-clicks.

In the Pro versions being able to customise shortcuts and make your own toolbars does help.

Get these right and colour becomes less important.

Acorn