Mix-and-match customization

Can anyone give me a single coherent explanation why there is even an Armor Core system in the first place? There’s no universe where they’ll get away with making us unlock the same cosmetics multiple times, so why even bother disallowing a mix-and-match system?

Just let us pick our main armor pieces alongside all of our other pieces.

“Oh sick, dude. Really nice samurai helmet on your samurai armor. Really love the way your Mark V helmet complements your Mark V armor.”

Why didn’t they just give us like 3 full armor sets in the base game? We’re all just unlocking the same non-customizable stuff in the same non-customizable order.

Can anyone possibly understand why they did it this way? Even from a market perspective, it doesn’t make any sense. A few minor changes could increase the revenue stream from just a few “whales” to almost the entire enthusiastic fanbase. Really wacky.