As clearly stated in the paper you cite, two types of CD8+ T-cells exist at MS lesions, regular CD8+ T-cells and CD8+ Treg cells also of course regular Treg cells. The regular CD8+ T-cells are not good, they express CCR5, the CD8+ Treg cells do not and kill off CD4 cells that are causing the inflammation that damages the myelin sheath.

Leronlimab steps in shuts down CD4, CD8+ T-cell and macrophage trafficking that's causing the inflammation. But what about those poor old Tregs? No inflammation no need for Tregs that are so lazy they're allowing MS to continue anyway.