In my 20 years in this field I can easily count on one hand the times a diagram like this has been useful. I’ve seen more cases where they were clearly created to satisfy some exec that wanted to see it and never updated again.
If you are doing any architectural work, whether at the software or infrastructire level, I fail to see how you can deal without diagrams to 1/ understand interactions between all system components 2/ make your changes understood and validated by relevant people.
Granted I speak about real, useful, technical diagrams, whose purpose is to convey useful information and highlight data flows. Not marketing diagrams you may find on marketing presentations, but this is not what this discussion is about.
In my company, we generate diagrams from data coming from external referencials that ARE source of truth, by process. Not the perfect solution, but much better than representations of a reality that has already moved miles ahead.
In my 20 years in this field I can easily count on one hand the times a diagram like this has been useful. I’ve seen more cases where they were clearly created to satisfy some exec that wanted to see it and never updated again.