I have a test account that I log into in situations where I need to try something out, and I log into that using a private browser window. That is always possible, but I think there’s a lot of cases where I’d just notice things if my access were “regular” by default.
It also doesn’t prevent me from accidentally violating constraints I set up on purpose (like the tag rules, or posting in categories which are supposed to be read-only).
The other alternative — making my main account be a regular account and having a separate admin one — would solve that, but in practice be a hassle, and also I’d miss notifications for flags and for private messages.