Indeed. If you ever poke around in the app you’ll spot platform-specific code all over the place. Sublime Text is one of the rare non-native apps that spends time caring about each platform, which generally gives them a huge boost when it comes to adapting to the platform.
Your last sentence….. The macOS version is awfully not-Maclike in ways that matter and that you can’t fix with plugins (last I checked). They’re pretty far from a native Mac editing experience, and nothing about Sublime actually requires that divergence; TextMate 2 is still a much better native-feeling experience.
Edit: that said, I’ve now realized it’s been at least three years since I tried Sublime, so this could be improved?
I mean I know it doesn't look very Mac-like but text editing matches native controls almost 100%, and they put in at least minimal effort to make windows and state restoration and whatnot work correctly–it's far better than most other cross-platform apps. It's no TextMate, of course, but is there anything in particular that's bad aside from the UI?