This is just me bullshitting, but I imagine you'd want to continue shipping a simple interpreter and some kind of script for the computer opponents and use a hypothetical learning system to generate the scripts separate from the game you ship. The AI code in the game would be simpler, the scripts could be easily patched, users could generate their own scripts, etc.
I think you could probably generate and hand-tune a number of situational scripts and let a learning system decide how best to chain them for particular circumstances (e.g. if the opponent is Character A, the computer is Character B, the computer's relative health is much lower, and Character A has a full super combo gauge, then it learns a particular sequence of scripts that proves effective in replays).
I think you could probably generate and hand-tune a number of situational scripts and let a learning system decide how best to chain them for particular circumstances (e.g. if the opponent is Character A, the computer is Character B, the computer's relative health is much lower, and Character A has a full super combo gauge, then it learns a particular sequence of scripts that proves effective in replays).