If you actually looked at the Hallock video with the original slides from November, the majority of the promised performance gains came in the form of microcode updates to fix the fact that High Performance and Balanced power modes weren't giving the same performance. Most reviewers already caught wind of this during launch day and ran their benchmarks under High Performance Mode, so what you saw on launch day from reviewers where Arrow Lake was performing better was already 98% of the potential of Arrow Lake.
The rest of the updates were either random edge cases or only promising an overall performance gain of single digits. Which it looks like has already occurred, about 3% performance improvement across the board. This is pretty much all we are getting.