I've only been in a couple of cylinders over the last few years, but...
As my eyesight gets worse, I've been running the tool at a lower rpm to match.
Surprising how much difference it makes in the aluminum sticking.
Another thought is if you're getting into the hard coating.
You might keep a burr for skimming the plating off and then swap to one that hasn't been in the Nikasil, to finish the aluminum work.
Even just a couple of sweeps into it makes a noticeable difference in how the burr gums up.
Using the burr in a muffler for de-catting will dull them too.
Rust or any oxidized metal will dull them also.