My pet hypothesis is that the invaders from Yamnaya culture were still fighting the aboriginal Europeans (like Ötzi) back then, at least in more isolated places like the Alps. Elsewhere the disputes have been mostly solved, by either peaceful agreements between local aboriginal vs. invader groups or wiping out one of them. Ötzi was one of the deaths caused by those fights.
If my hypothesis is correct, a DNA analysis of the blood in his gear should reveal something like:
- knife, quiver - the three individuals should have quite a bit of Steppes-related ancestry
- back of his gear - likely a comrade in arms, it should be mostly Anatolian farmer-related like Ötzi
Another thing that interests me is that Ötzi ate relatively well. Biopsies of his stomach show a balanced diet of grains, meat, herbs.