Messner is a newbie. There has been a long, rich tradition of solo mountaineering. Consider Hermann Buhl who did a first ascent of an 8,000 meter peak in the 50s (Nanga Parbat, I believe). Later perished while climbing.

What about Alex Honnold and his solo, high grade technical climbs? He waltzes over stuff I can only dream about......

I read about Buhl when I started climbing - probably induced me into some of my solo trips, which fortunately ended OK and I became more prudent without serious incident.