Supply constraints are terrific for margins. That's why cartels are so profitable (and generally illegal).
Stellantis is battling VW Group for #1 in European vehicle sales. EU 95g effectively requires 20% of vehicle sales to be EV, so the two are pretty close in EV sales as well. I haven't seen anyone in Europe really go beyond the quota yet, nor do I expect to. The next couple years will be very interesting because the quota barely moves after taking huge jumps in 2020 and 2021. S Curve fans could be in for a real disappointment.
Fiat bungled the EU 95g quotas early on and had to buy papal indulgences from Tesla. This was mostly the fault of Sergio Marchionne (RIP), and it led to PSA opportunistically swallowing FCA to form Stellantis. Tavares is a shrewd operator, but he's got a crazy assortment of brands which might need some thinning.
Outside of Europe VAG is much stronger, especially in China. Neither is a major player in the US, though Stellantis has a couple of strong brands in Jeep and Ram while VAG fills some nice high end niches with Porsche and Audi.