I don't agree that every manufacturer has a halo vehicle. What's Honda's? What's Toyota's? What about Hyundai? Kia?
Furthermore, I think you missed MY point. The F150 has been the top seller without a "halo" for many decades. The Raptor was not created as "halo" vehicle. It was created as "niche" vehicle, as were all SVT vehicles. The Raptor outsold any/all expectations because it was so appealing to enthusiasts. Even enthusiasts who hadn't considered a Ford since their 1993 Mustang Cobra. Ask me how I know.
Sticking the 3.5EB in the Raptor is definitely a marketing move, though, one that was meant to put a "halo" on an engine with little interest to enthusiasts. That much we can agree on.