Interesting perspective FTF . . . and perhaps I am misinformed here.

I have always been under the impression that hypereutectic alloys were created to allow for tighter machining tolerances over eutectic alloys in like-for-like 'cast' processes:
KB Silvolite
for the benefits that you have listed.

But I am also under the impression that forged pistons and cast pistons have very different thermal properties such that given the same aluminum alloy a forged slug can be machined to tighter tolerances then a slug cast from the same material.