In some respects this seems somewhat inevitable, the 787 has always had some sort of problem, and much of its lifespan has travelled through the period of the supposedly ‘old’ profit above quality Boeing. The one that led to the MAX disasters.
Constant complaints about Charleston’s production values, quality, worker dissatisfaction, inexperienced managers, previous battery issues, even early wiring fires have all played their part. I’ve seen with my own eyes the rapid deterioration of some 787-9 interiors – at three years old they’re showing dramatic ageing you’d never have seen in the past.
The latest problem is far more fundamental, with structural problems in the rear of the aircraft fuselage (see the details in this article: https://aviationnews.online/2020/08/28/news-easa-max-787-structural-issuesunited-anz-etihad/
The FAA says its going to conduct a wide ranging investigation into how the problems on the 8 affected aircraft have come about and wether or not more needs to be done to rectify them in future. It also wants to look at prior aircraft and isolate if any issues exist with older airframes.