I think there is a misunderstanding of what bloom is. Bloom just adds the glow around bright lights like neon/emissive materials or bright reflections. And OP showed in one of his replies a video showing the differences of each method of getting shiny objects. His material is very different compared to others.
The only real way to replicate this material is to put it in a dark area of your game and put a bunch of bright lights around the object you want to be shiny:
That being said though, while it looks really cool, I can only see a limited use case in some places for this material.
Cant you use custom split normals for this? afaik you can change the normal of each individual face in blender, so the splitting part is kind of confusing to me.
Did you not find any specific option? I saw something related to the topic of this post in the latest video, and it seems this option is superior to all the options mentioned above. It would be interesting to find out how
