I’m familiar with your site and appreciate it a lot, and I don’t dispute anything you said, but that does not contradict anything in my comment. Those people you mention who apply the rules differently everywhere are inflexible and unwilling to give leeway or look further then their own way. This is a cultural issue in my opinion and can explain most of excessive bureaucracy here. You’re also talking specifically about the ausländerbehörde, which is one manifestation of bureaucracy here, there are many other forms.
My experience was a bit different. For example, the immigration office accepts almost all applications in the end (over 95% according to their stats). They make all sorts of exceptions in the applicants' favour. The Bürgeramt, the Ordnungsamt and the Arbeitsagentur are the same. They huff and puff and make an exception "just this time", every time. The inflexibility is an act, unless you're being difficult (from their point of view). Then you get the least charitable interpretation of their directives.
Against all expectations, German bureaucracy is very "vibes-based", specifically because it's full of humans. It's predictably unpredictable. You rarely get the downside of digitalisation where "computer says no", because a human is deciding your fate and can be convinced to give you leeway.
The bigger issue at least for me is speed. The uncertainty of human decisions is magnified by the weeks-long delays. A missing document is a big issue when bureaucracy has a 4-8 week ping. That is of course if the case worker doesn't shrug and give you what you want anyway.
I think that German bureaucrats choose the path of least resistance. Most of the time it means giving you what you ask for.
When you get the short end of the stick, a letter from your lawyer can make it abundantly clear that giving you what you want (and faster) is the path of least resistance.
