Hi Aldo,
The spark arrestor screen was a "production option" on quite a lot of outdoor equipment engines sold in the US. The engines were not test-run in the factory, and I seriously doubt there was a different carburetor used when the screen was fitted, so it seems unlikely to me that a clean screen will change the tuning noticeably.
Because the spark arrestor screen was a bushfire safety feature (albeit an optional one), I will not comment on the merits of removing it. Personally I have never owned a machine that had one fitted.