This is the source of your mistake. Users don't desire to have the same UI across different OS environments, it's only an app's developers that care about that. Cross-platform UIs are inarguably a worse user experience than UIs tailored to the conventions and designs of each OS.
A Mac app that doesn't actually feel or behave like a Mac app is not a good Mac app. The same is true with tvOS apps like YouTube and Prime Video that don't actually feel or act like good tvOS apps.