I’ve seen an economist (sorry, I forgot who) who said that the natural rate of inflation is slightly negative to match the average increase in productivity so that an hour of labor stays the same price for a certain job over time. Anything higher is from governments and banks skimming from devaluing currency.
I can sorta see perhaps why the gov’t wants an average slightly above zer0 in addition to why a gov’t deeply in debt likes hidden taxation.
That would be that as there is natural variability in the inflation rate, going below zer0 might send the economy to a place not desired by the majority of the oligarchy.
Having to develop financial strategeries that can weather both deflation and inflation could be more complex and problematic.