Etruscan→Latin

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So that's the Etruscan alphabet, the alphabet from which the Latin alphabet derives. The resemblance is pretty close, but what happened to the letters ????, ????, ????, ????, and ????? Why did they just vanish into the æther between the Etruscan and Latin alphabets? You can't tell me that they were dropped only because Latin didn't have those sounds, because Z remained for centuries without representing a native sound in Latin.

I cannot see the other glyphs, however :(
Esh, she etc. were dropped because Latin hadn't these sounds.

Z was reborrowed from Greek, used only used with Greek words (probably sounded like /dz/ ).

But now we have a 26-letter alphabet awkwardly shoehorned into writing every language ever.

Oh, here's why. That's the old Etruscan alphabet, back when it was 1:1 with the western Greek alphabet. Over a few hundred years, the Etruscans took an axe to their alphabet until it looked like this:

???? ???? ???? ???? ???? ???? ???? ???? ???? ???? ???? ???? ???? ???? ???? ???? ???? ???? ???? ???? ????

This is also why alphabets like Oscan and Umbrian were so messed up. By the time they were derived from Etruscan, Etruscan had dropped a bunch of useful letters.

...But that still doesn't account for the lack of ????, ????, ????, and ???? in the Latin alphabet from the very beginning.