I'm not sure that's completely accurate - Honnold free solos a lot of stuff. Most of the stuff that Marc is onsight soloing is M7 and below - that equates to about 5.11 and below - and Honnold routinely onsight solos around that grade. And historically, Honnold has climbed for similar reasons - he just loves it, and often didn't care much about what people thought about his solos (except for his biggest ones). While MAs were obviously nuts, being on ice and snow and not astounding quality rock - I'd say they're pretty good analogues to each other in terms of commitment, risk, motivations and approach - we just don't see the videos of Honnold's <5.12 solos because they're not notable considering how far he's pushed the bar.