To me, the thrust of the article is on making sure human factors are incorporated into flight certification process. As they highlight, although uncommanded MCAS input was part of the certification tests, it was only marked as a 'major' risk rather than more severe classifiers. This wasn't because of any phenomenal test pilots, but just because the FAA (rather than Boeing) guidelines behind the certification assume immediate assessment and diagnosis of the issue.
The report goes into a lot of depth about other human factors, for example, how transport-category planes should have straightforward highlighting of the primary issue since often the primary cause bubbles through various interconnected systems, and the main pilot response tends to be to identify the root cause under stress and then having to fix it.
To the extent I could re-summarize the report, I'd say "Plane Certification Processes Must Consider Real-World Scenarios And Factor Human Response to In-Flight Failures in Plane Design"