Why would traces of a hypothetical pre-Moon civilization be nearly impossible to find today?

Answer

Their traces would be buried under immense thickness of subsequent geological strata, likely distorted or obliterated by billions of years of plate tectonics and erosion

Evidence from billions of years ago would be subjected to immense geological processes, including erosion and plate tectonics, burying and likely obliterating any physical traces of a civilization that might have existed then.

Why would traces of a hypothetical pre-Moon civilization be nearly impossible to find today?
GeologyevolutionastronomyMoonPrehistory