Maybe there is more to that. It's been more than a year since Llama 3 was released. That should be enough time for Meta to release something with significantly improvement. Or you mean quarter by quarter the engineers had to show that they were making impact in their perf review, which could be detrimental to the Llama 4 project?
Another thing that puzzles me is that again and again we see that the quality of a model can improve if we have more high-quality data, yet can't Meta manage to secure massive amount of new high-quality data to boost their model performance?