As someone that had experience on both sides, AndroidX is roughly functions as a middleware that exposes roughly (but not always) the same set of API from the frameworks. Nobody sane would use the bare system framework as it’s a nightmare for backward compatibility and for handling device capability.

You’d still use the SDK the compile against, but AndroidX provides a nice wrapper that handles the aforementioned issue. It’s a separate library and not tied to the SDK.

Like everyone said, really dislike the press side button to show control center changes, used that more than the widgets stack.

But they did bring back persistent icon? On the top of the clock. Now i can go to now playing by just tapping that icon.

Oh yeah i also dislike how i need two more taps to go to music playlists.