I notice a lot of people greet new user's posts a bit abrasively. Not exactly a warm welcome. Not everyone hits the ground running in the right direction, so to speak. We all started somewhere.
The passive-aggressive approach would be to hide post count within threads... since it could influence how someone responds to someone else. It's wholly unimportant with regards to forum interaction, anyway. It shouldn't necessarily be used as a marker to determine how you should respond to someone.
The preferred approach is just to... not treat new users poorly, and understand even those of us that could be considered "established" and longtime users had some silly initial posts, and even made that run to 50 ourselves. Mods will address the low-effort runners, and users can "moderate" by offering advice or initiating substantial conversation to those that look like they may be rushing a bit too fast out of the gate.
There are several members that do this exact thing. Some in the open and also through PM's.
I have spent a lot of time doing this before clipping post count.