This is a genuine question and worth answering honestly.
The coordination is done for you. An Aangi blouse and saree bought separately have to match on three levels: colour depth, fabric weight, and embellishment density. Get any of those wrong and one piece dominates the other. In a set, those decisions are made by the artisans who made both pieces in the same workshop, with the same materials.
The Gota work echoes across both pieces. When Gota Patti borders on the blouse and the saree pallu are worked in the same session by the same artisan using the same metallic ribbon, the finish is consistent in a way that two separately purchased pieces rarely are. The metallic tone, the width of the ribbon, the tension of the stitching all identical.
One decision instead of two. Choosing ethnic wear for a wedding function is already a multi-variable decision. A set reduces it to one choice: which set fits the occasion and her style. Everything else blouse fabric, saree drape weight, embellishment level is already solved.
The price reflects the set, not the individual pieces. Our Aangi saree sets are priced as complete outfits. Buying the same Aangi blouse and a matching saree separately would cost more than buying the set. The set price is not a premium it's a saving on a coordinated look.