I found that Wilbur is excellent for making maps for Cities: Skylines using heightmaps from terrain.party

There however is 1 problem: Due to the system used, the maps basically show up as 90% steep cliff, absolutely awful

What i basically need is not to smooth the map so it's not jagged, but to reduce the height difference between low areas and high areas, for the entire map

I found that you can do that with the "remap altitude" option but that one is weird and inaccurate, and found a similar thread, where it was recommended to use the set value option, but i see that it won't work for the entire map, just a selected area (basically you need to have an area selected otherwise it doesn't work)

Basically i need my terrain "squeezed" vertically, so that the difference between lowland and highland isn't so steep