It's not an unreasonable question. From reading the TSB report stainless steel used on the UH-60 was replaced with more expensive titanium. As I've never heard of an aircraft that was 'too light' perhaps it was for weight saving. Or perhaps there was another perfectly sensible reason to switch. The trouble is the TSB don't explain why that design choice made perfect sense at the time.
It would be a service to all those other dedicated designers out there, who are perhaps working on components for the next generation of helicopters, if they could better understand those decisions.