Why would much of an eternal inflation and string landscape multiverse be unable to support life?

In the context of the eternal inflation and string landscape multiverse, much of the multiverse is considered unable to support life because the physical conditions vary significantly across different regions.1

In this framework, string theory suggests that the configuration of compactified extra dimensions determines the physical constants and vacuum energy within a given universe. Because these configurations can transition, the multiverse contains a vast array of universes with different laws of nature. Many of these resulting universes possess physical constants—such as the cosmological constant—that are incompatible with the formation of complex structures, stars, or the biochemistry required for life.12

Consequently, life is expected to exist only in those rare regions where the physical constants happen to be compatible with life-supporting conditions. This perspective relies on anthropic reasoning, which posits that observers will necessarily find themselves in a universe that permits their existence, even if the vast majority of the multiverse remains uninhabited.12