I think it's more about positioning the Tonale upscale from the Hornet , which is supposedly getting both powertrains and a lower starting price (although that could still change as well).It's how corporations become profitable now.
Alfa will get tax benefits that will contribute to the bottom line more than selling that engine in the US. It's a nihilistic view to say the least, but popular amongst corporate executives for valid reasons.
I don't agree with all the reasons, and think there are better solutions, regardless this is how it is.
Although.. I sorta suspect in this case the issue isn't just financial. I am guessing with Dodge and Jeep using the Alfa 2.0 in various forms now and having them outsell Alfa by a huge margin, combined with the uncertain supply chain, Stellantis would rather prioritize the engine for other brands, while also not jeopardizing availability for Giulia/Stelvio production. But I don't think that would ever be given as a public reason because it makes them look uncertain/weak as a corporation.
Higher starting price, more standard equipment, etc. is likely part of the brand strategy. Alfa is not supposed to be competing for Dodge customers. Audi Q3, BMW X1, Mercedes GLA should be where the Tonale is aiming.
As for a need to drop the 2.0 because of supply constraints or improving CAFE numbers, nah. There isn't enough potential Tonale volume to make any difference considering the scale of Stellantis operations and global demand for the GME 2.0.
Here's something to consider: Stellantis sells about 6.5 million vehicles annually which is almost 40% more than GM global sales. They're big. Really big.
Alfa Romeo annual global sales of 29,000 represents 0.4% of Stellantis' annual volume.
Basically, the Alfa brand is a rounding error. Our favorite little brand is lucky to even exist. Tonale is a very good thing and will undoubtedly help brand recognition, profits, and hopefully long term brand viability.