Why is Red channel of Gray (packed texture) Previewing as RED?

[ClockworkOcean]

This is the closest I got to an answer

Why black/red colors in materials' monochrome preview nodes?

I am assuming whatever shader they are using for the node preview is converting it to a vec3 and only filling the red channel, same as I described above. Why’d they change this? No idea, maybe it was a bug they never bothered fixing

It’s not going away…