That's one possibility, along with the manufacturing process used by the big movie houses.
Extrusion molding of parts is prohibitively expensive to most, so vac forming or fiber glass molding or 3D printing is as close as we get.
The ability to to use a vast array of materials , flexible and rigid is where the production costumes are at so there is a disparity from the start.
Over time some of the makers have improved to get closer in design and measurements and there is certainly an abundance of reference material in screen shots and actual images of screen used armour in parts and from every angle, the rest I guess is up to the individual makers interpretation.