It only says that below the main title, and from the wording it's also unclear if that's what it's actually intended to show or just the cutoff for a language being represented.
Like, it could be interpreted as showing L1+L2 speakers of languages with >50m L1 speakers
The chunks are language families. Turkish is the only Turkic language which meets the cutoff; wikipedia says the second most spoken language in the family is Uzbek, but that only has 44 million speakers (native + second combined)
I don't recall it ever having been used to bring people back after they've been killed; usually it's only relevant in weird circumstances like when Scotty showed up in TNG
Space distortions