I agree with your suggestion conceptually, but the starting point of a decision tree strongly depends on many factors: which version of the software is being us

I agree with your suggestion conceptually, but the starting point of a decision tree strongly depends on many factors: which version of the software is being used, how the software was compiled, running with what OS, which what patches, on what hardware, under what environmental conditions, in support of what application usage patterns, and what load, etc. Merely capturing the (potentially) relevant input conditions becomes challenging, never mind the process of eliminating irrelevant variables. And that's all premised on the concept that a problem is recurring (rather than some fluke that no one else has encountered). I think that's why Stack Overflow websites focused on shallow conditions flourish -- the deep dives are usually specific to a given situation.