How to invert gloss on a procedural texture? How can I make the upper layer/exposed part glossy. Currently I have the
opposite, the lower part/holes is glossy, while the more exposed outer part is
rough.
What I want:

What I have:

I suppose it's glossy because it starts melting sooner.
In your node setup, the roughness (a.k.a. glossiness) comes from a color ramp:

So the simplest solution seems to be replacing black with white and white with black on that color ramp. At least if you properly diagnose your problem as being the opposite to what you want - because inverting those colors will invert the roughness.