YSK: Browsing "ALL" at work might get you pulled into an office, even with NSFW off.
Why YSK: It appears several Lemmy Instances are flagged as suspicious and at least 1 instance intentionally using the name of ransomware. A couple of the big enterprise monitoring suites (Fortiguard, ZScaler) will flag your account and may end up with you being pulled into an office for an explanation, or worse.
TL;DR: Keep browsing to your local instance at work for now.
Really depends on the place of work. I work in the IT of out company and my PC isn't monitored. My door is constantly open though and there are a lot of people passing. Me looking at the screen is normal and part of my work. Me looking at my phone is always seen as me not working.