I don't want to get into a long argument about this, but....
Compare your OSM map to the skin's default Google Map, like here:
https://jefftucker.net/saturn/maps/
In Saturn, the map is centered horizontally
and vertically.
Now grab the lower edge of the browser window and drag it upwards. With your OSM map, you get scrollbars - the map display doesn't respond to the new size of the viewport. Even a CTRL-F5 refresh doesn't fix it.
I'm on a solid, fast connection, but zooming in OSM often produces what you see in
gray.png.
As I said, OSM is fine in heavily-populated areas. It gets very sparse elsewhere. Even in my own neighborhood, in the busy northeast corridor of the U.S., OSM is almost useless. Compare the two screenshots -
gm.png and
osm.png.
I don't like adding things to my skins that don't work very well.