Agreed - and I've read that Samsung engineers have been unable to reproduce the failure. In my line of work, if you haven't reproduced the issue you haven't fixed the issue - so this leads to questions about the judgement surrounding the first recall in my mind if they hadn't reproduced the thermal runaways. My unit was (initially) deemed "safe" due to the battery manufacturer being ATL, and I've never seen the battery rise above 31degC even during fast charging. It must be a very specific set of swiss holes lining up to result in the failures observed, perhaps the owner(s) dropping the unit in a certain way could be one variable?
I note Samsung have said they will throw everything they have at identifying the fault and ensuring no repeat in their future products, but what if they fail to for possibly the reasons you outline (they give up to reproduce the fault)? The big burning (pun intended..) question in the battery industry is will they share the results of their investigation. I think they have no choice. Trust has been lost, they need to rebuild it, and transparency is a pre-requisite in the trust rebuild. They've already lost massive ground to Apple now and the new Google Pixel phone...I hope they pull it back from the brink; they were clearly leading Apple in terms of innovation (Apple have been on the back foot for a while now to Samsung imho).