Why only that model for a forged frame? I can guess, for what that's worth. First, of the solid frame models out there, the Remington is by far the most popular. Second, forging the frame of a Colt-style open top won't make it strong. It might make it stronger than it was, but it's still not going to be strong on any absolute scale.
You already have a bajillion steel-framed Remington replicas out there, and I've never heard anyone say they weren't plenty strong. I wonder whether the forged frame really would be any stronger than a good investment casting, and if so whether the difference would be enough to matter. I guess time will tell.
But, of course, Uberti's point is not whether forging is technically better (assuming investment casting is good enough to be safe, as it seems to be). Uberti's point is whether a forged-frame Remington would sell. They'd make 'em out of Monel bronze, or titanium, or aluminum, or some weird science fiction ceramic composite, if they knew they could sell enough of them.