HSL as a local adjustment?

I’ve been using HSL/yellow to reduce luminance of night sky light pollution - much the same as a physical ‘light pollution’ filter - but I’d love to be able to limit it to only the area above the horizon and not affect star/planet colors. This is one of the things I need PS layers and a graduated mask to accomplish, but if PL could do the same…
I realize that this is a big ask, but please at least consider it for PL3.