I stand corrected.
What it doesn't give you, however, is access to the control surface internals, i.e., to create new control surface "drivers" inside Ableton itself. But of course, that's currently the ONLY thing Bitwig lets you do with their API.
You mean Max standalone?
Max For Live sure does "give you access to Ableton's UI or API".
https://docs.cycling74.com/max8/vignettes/live_api_overview