Mountain biking is a dangerous sport….etc etc. even more so on a DS where people are “hammering it” . If your riding the course and you know there’s little or none “official” marshals, then yeah you’ve got to expect everyone else to carry on around you really. How many of the oncoming riders were first aid trained, and even if they were, would you expect them to come to your aid given that you’re riding a track with all the dangers I’ve pointed out.
If you’re not prepared to ride without that aid instantly available should you crash, then find a suitable location/ event more to your taste, if not ride at chicky and accept the consequences of your actions