as far as I’m aware, the old client doesn’t provide any method to hide the route waypoints. As it is not being actively developed at the moment, I don’t think that will become an option anytime in the future.
I tried importing the .gpx-file provided on the Klettgaulauf-website you linked, and it rendered it only containing 5 Waypoints. Together with the map setting to display distance markers (accessible via the “Settings”-cogwheel in the top right of the sidebar), in my eyes this gives a very nice overview over the route.
Displaying distance markers is unfortunately a browser-related setting, i.e. averyone would have to turn that on for themselves
As for using the new responsive client instead, I’m also not aware of hiding waypoints being a feature and I don’t know whether it’ll become one in the future. If you want to encourage that, feel free to open an issue in the corresponding repo. However, the file import is currently not working as intended. We’re aware of it but cannot guarantee a time frame for fixing this.
That being said, I’m not completely convinced the ORS is the correct tool for what you’re trying to accomplish. As delighted as we are to see you using it, as you stated yourself, you seem to want a static display for a fixed route - and as the ORS is a routing service, it is not directly built for this kind of application.
I hope this helps you out,