Lorica hamata / segmentata

[Titus Petronicus Graccus]

What I don't understand is why Segmentata completely disappeared in the middle ages.
Wouldn't a quick-to-make cheap armor be very useful to arm the militia and levies?

I did a study of this in University. Seems (at least to me) that the development of Armor had much more to do with fashion, rather than it's ability to deflect weaponry aimed against it.
Not a truism of course, just an educated guess.