This sounds like more correlation than causation to me. There’s a similar statistic people like to quote in regards to backcountry skiing - that you are more likely to be in an avalanche if you have taken an avalanche safety course. Sure, there’s a correlation. But when basically everyone who backcountry skis regularly has taken such a course, and the people who backcountry ski infrequently are less likely to have taken a course, you can imagine why such statistic is true. Furthermore, advanced backcountry skiers are way more likely to be venturing into more complicated avalanche terrain that has more inherent danger.

It would be better to measure the accident rate in a more controlled setting, like accidents per gym route climbed. I can only surmise on what the results here would be. I don’t doubt that experienced climbers get complacent, but new climbers also are new to it and likely lack some knowledge to keep things safe.

I suspect that with experienced climbers, they are probably climbing way more frequently than inexperienced climbers (which you would need to account for to suggest causation), and also doing more dangerous routes. New climbers are less likely to do alpine routes where you encounter climbing when fatigued/sleep deprived, weather concerns, rock fall hazards, complicated descents, etc. And brand new climbers are hardly ever climbing trad routes, especially with marginal protection.

Side note, but as someone who nerds out on reading accident reports, climbing accidents are hardly ever caused the gear failing. Even old ropes damaged by the sun are super strong, and it’s typically quite obvious when gear is wearing out.