[Nevermark]

> The density in the observed universe is used to extrapolate the number of galaxies in the non-observed universe.

The unobserved universe is likely to be many orders of magnitude larger than the observed universe. It is possible that it is unimaginably larger.

Technically, it is possible that the unobserved universe is infinite, however whether that is a credible option depends on individual scientists informed intuitions. We simply have no experimental or theoretical evidence either way at this point.

So there is no estimate of how many galaxies there are in the universe in toto.