On one hand, I have a backoffice that gives access to the staff to everything related to the customers, but on the other hand I'm supposed to believe that being able to 'impersonate' a customer is this highway to hell? As long as an audit log is held about who did what, this can go a long way forward.
Are you Series A? B? A decacorn? Sure, implement whatever distributed tracing dashboard analytics data lake serverless microservice monitoring solution you can dream of. But this is good advice for early stage.
At a certain scale it needs to go away though, or be very tightly controlled/audited like you say.
Not just the ACLs you've established internally for which personnel can do what, but ensuring that you have express permission of that particular customer to be looking at that particular data of theirs, on that occasion.