In spite of the arguments and hair-splitting I stand by my comment: if you keep soloing at a high level, sooner or later something is bound to go wrong. I know a number of climbers who used to solo up and down 5.11's but gave it up and are glad they did. I myself used to solo up to 5.10 but gave it up after a couple of close calls.
No one can climb at a “high level” indefinitely, no matter the discipline. If people are honest with themselves and moderate the level at which they solo as their overall abilities change, I doubt their death rates will be significantly higher than any other climbers. Somewhat higher sure, but not significantly.
I agree, but what does "high level" mean? Honnold is a 5.14+ sport climber, a vee-double-digit boulderer. So, when he solos even at his highest levels (I think that Phoenix is his hardest? 13a?), it is roughly the equivalent of 5.11+ climber soloing 5.10a. Not easy, but not what we would call reckless, either.
For the most part, soloists are not soloing at their physical limits. Dereck Hersey was one of the few who did, as I recall reading in his profile in the book "The High Lonesome."