FWIW: To give some context to this discussion, while the Collings FAA LHFE exemption required various documents and programs, like an SMS program, it was still basically a Part 91 private operation. So any comparison to a 135 or 121 culture would be amiss. Since the aircraft are operated on a Special Airworthiness Certificate, the specific FAA exemption document details the operational and maintenance limitations for the operation in general and for each aircraft. So there is no lack of specific FAA rules and guidance.
Having volunteered at a number of similar operations as an A&P over past years, to include the CAF in its heyday, I found each one to be different “culturally.” And while I’ll wait for the factual NTSB report docket to be fully released before making specific comments, I think if one were to predispose themselves to view this accident from the vantage point of this is an old and unique personal aircraft, whose pilot was one of the most experienced in the world, and who also performed/signed off most of the maintenance, I believe some of the “why” questions may be answered easier than trying to compare this situation to a regimented for-hire operator with “rogue” mechanics running around.
And for those who had questioned, this aircraft was inspected under an FAA approved inspection program which I believe consisted of an Annual inspection with various scheduled inspections in between the 12 month Annual requirement and it was maintained per B-17 military documents. I think the actual FAA exemption documents that list these requirements are still available on the FAA or similar website.