I mean, this seems like a weird conclusion. People like believing in stuff, so they believe in stuff; arguably the nature of the stuff is irrelevant. Astrology is just one of thousands of religious/pseudo-religious systems. Romans preferred to do their divination through the study of entrails and birdwatching; must those also have been useful (except in the context of providing belief and ceremony)? (They did eventually kind of adopt astrology, but it was viewed as a suspect foreign practice at least until the early empire).
> Like the “flat earth model” is actually extremely useful if you don’t intend (can’t) travel significant distances - gives you a coordinate system
By the time anyone really had coordinate systems, educated people knew the world wasn't flat. There's this persistent belief that the world not being flat is a relatively new discovery (I think people confuse it with heliocentricity), but this isn't true. Modern flat-earth-ism is a creation of the 19th century, not a continuation of some traditional belief system.