
Well I don't know about SALH suitability for C-RAM, it's kinda unprecedented AFAIK, not going to count out 2.75" rocket airframe, but US Army doesn't appear to be asking for IFPC to keep up with the tip of mechanized formations, as I understand it's still for the semi fixed sites like forward logistic hubs that you can't entirely get rid of. But I'm guessing they want the minimum protection configuration to have as little footprint as possible so there's the option to disperse even more but still have some defense to create uncertainty for attackers. From that I extrapolated that they may also find more affordable interceptors to be more appealing, for what they need to defend.
APKWS with little to no modification can probably work for C-UAS, while also contribute to ground combat. It's certainly possible to find a place on M-SHORAD IMHO.