Really? I think that in most orgs up to medium size, you expect senior and especially staff engineers to have that scope
They wouldn't be able to draw it all onto a whiteboard from memory. But give them a half day and they will have mapped out the data flow
The bigger the org, the more specialized they want you to be.
I've seen these people rapidly disappear in the last 5 years at a big tech co. Old UNIX heads that had experience back to the 80s being made redundant. Who is replacing them? Mostly offshore 20 something year olds on a fraction of the salary a tenured person had, being told to just follow runbooks, pasting the runbooks into Claude or ChatGPT. These people can't explain anything, didn't really cut their teeth on doing things out of curiosity, and if asked a question, will just be playing copy-paste-back-and-forth with a LLM.