I care very, very much about safety at work.
By safety, I refer to a few specific types of safety - technical safety, safety to be authentically yourself, psychological safety...
Especially in programming, it's vitally important for all players to feel safe and protected to speak their minds, raise questions or concerns, and most importantly to try new things and take risks. Although the agile manifesto does not explicitly speak about safety, I believe that by valuing individuals and interactions over process we must value the safety of those individuals and foster positive interactions between them to succeed.
It's possible that most of your work day is spent at home on a computer, interfacing with teammates via Slack or on Zoom. If this is the case, the psychological safety you may experience as a member of an agile team may be more tenuous than when you were all in the office together. Because we spend less time "doing business" in-person as a collective, each interaction you have with your teammates becomes heavier with significance and meaning.
This is why there is no room for passive-aggression in teams that value psychological safety. The moment that passive-aggression shows up on a team, psychological safety is damaged for all members. Even if that person being passive-aggressive is only doing it because they themselves are experiencing fear or insecurity because of their own lack of psychological safety on a team.
Passive-aggression can be both a symptom and cause for decreased psychological safety on a team. Its important that you follow-up with that individual and make sure you understand what's going on when this starts to manifest.