`w` not working on Buildroot

I'm working remotely on an embedded device running Buildroot. My colleagues are working on this same device, so it's important to know who else is logged in. For a previous project (running on a non-embedded Ubuntu machine) with the same conditions I used the w command (or alternatively who) for this. It shows a list of all active sessions. Including my own. However, I noticed that for this Buildroot platform who is not installed, and w doesn't output any sessions. Despite several sessions being active. It doesn't even list my own!

$ w
 00:35:25 up 8 min,  0 users,  load average: 0.04, 0.04, 0.00
USER     TTY        LOGIN@   IDLE   JCPU   PCPU WHAT

$ ps -aux | grep bash
username    585  0.0  1.7   3424  2084 pts/0    Ss   00:28   0:00 -bash
username    596  0.0  1.6   3352  2068 pts/1    Ss+  00:28   0:00 -bash
username    623  0.0  0.9   2636  1204 pts/0    S+   00:35   0:00 grep bash

Elsewhere on this site I read that it might be due to not having admin privileges. However, when executing with sudo, or even entirely from the root account, it still does not display anything. Any idea why this might be?