Is Scout Radar bugged?

Simple question. In my continued adventures of completely certing out the ANT, I decided to try maxed Scout Radar with Stealth, and play support by parking in/around contested bases, imagining it being a great way to support the team while earning certs.

Except that isn't the reality. Every time I've gotten myself situated in or around a base, the whole minimap lights up like a christmas tree, but that's where the fun ends. The radar assist almost never ticks, I'm getting maybe 300-700 XP for every 5 to 10 minutes of providing radar, which leads me to wonder if it's even working at all.

One thing I notice in its description is that it provides the radar for "nearby allies". What exactly does that mean? Can you have a 200m Scout Radar, but allies have to get kills within 15-25 meters of you for it to do any good?

If that's the case, which it seems like it is, it's an incredibly unrewarding and thankless thing to run, especially when you could be providing the same recon as infiltrator, all while being able to directly engage enemy infantry at the same time.

Thoughts/information appreciated.