Yeah, the debris removes itself with time. But there is still some uncertainty around how deorbiting harms the atmosphere [1]. Immediate effects of a single deorbit seem to be quite low but having such deorbiting scenarios at a higher frequency could have some negative effects.
> Indeed, even in the worst-case scenario, the average annual global mean ozone loss is found to be between 0.17×10–4 % and 8×10–4 %, while the Antarctic local ozone concentration change can reach about 0.05%. Those impacts are negligible when compared to the impact of anthropogenic activities, in particular emissions of industrial halogen-containing substances such as CFCs, that caused a global ozone loss of 3-4% (since 1970).