Stellantis is like the new Step parent to a bunch of step children that were given up for adoption by their biological parents. Some premier brands but also a lot of second tier brands and smaller brands overall. I wonder if they can keep so many brands afloat. Over the last 20 years or so the larger MFGs have shed brands and consolidated.
They mostly keep releasing the same car under different brands, so the cost for brand differentiation with respect to actual car production is pretty much the same as if it was a single brand. They even add non-Stellantis brands to it, e.g. Toyota (for example, see their European range of small, medium and large vans).