10 years in the industry and i've never needed any diagrams other than the ones that my IDE can automatically generate from the code and configuration itself. Anything else is an exercise in futility and serves only control-freak managers.
I won’t question your claim about your personal need, but if you believe such diagrams only serve control freak managers, you are closing your mind to the many other possible reasons that diagrams need to exist.
This is anecdotal (so is your claim), but I have aphantasia - I cannot see with my mind. Diagrams are one of the only ways I can reason about some things that I cannot otherwise visualize in my head.
People communicate, conceptualize and learn in different ways, and that has nothing to do with control-freak managers.
It’s very similar with me.
When I’m grasping a new concept I spontaneously get a pen and paper and start drawing block diagrams to visual cause/effects, sequence of events/actions etc. Also when I’m trying to recall a concept, I have to draw a block diagram.
Same when I’m explaining it to someone. I have to draw, otherwise I lose my chain of thought within a couple of sentences.
I think yed's layout algo's are the best in the industry. Also, the extensibility is great (even in the free versions).
Of course, once you have an implementation, documenting the as-built configuration using automated tools that generate from your actual code and runtime system is the way to go.
Often, the thing worse than no mental model, is an inconsistent mental model sending you in the wrong direction.
The most productive tool I've found is: https://github.com/terraform-docs/terraform-docs
Otherwise there is a lot of cloud, K8s, and then microservices + app design (typescript)
Decent: