Seems like a pretty nice Docker-desktop-ish GUI to me.
One remark:
> Application looks the same everywhere, no mental mapping!
That depends on your perspective. If you are on one OS and this non-natve-looking app comes along, you have to mentally map it for your OS so it's none-nativeness requires mapping to the OS-nativeness.
If you, on the other hand, only work "in" this application and just take it with you regardless of the OS, then you would indeed not need to mentally map the application itself. But I doubt this application is used that way in isolation.
More importantly, however, working on : OSes frequently is rare. The developer of the app does it. I, as the user, dominantly use a single OS and want apps to be standard for that OS…
One remark:
> Application looks the same everywhere, no mental mapping!
That depends on your perspective. If you are on one OS and this non-natve-looking app comes along, you have to mentally map it for your OS so it's none-nativeness requires mapping to the OS-nativeness.
If you, on the other hand, only work "in" this application and just take it with you regardless of the OS, then you would indeed not need to mentally map the application itself. But I doubt this application is used that way in isolation.