This is key! There is no (by which I mean NO!) body of Buddhists on the planet which do not incorporate form of animism in their Buddhism, excepting those touched by Western Protestantism.
We tend to write it off as cultural accretion gathered from the native practices of the various lands to which Buddhism traveled. But, we never pause to ask why such “accretion” is so ubiquitous as to be a universal facet of Buddhism; might it not be indicative of something inherent to Buddhism?
(All this confirmation bias is going on while we systematically ignore, too, that there is no era of even South Asian where it was not also present.)