Totally agree with this (and most of CannedRat's post). It's exactly why the devs are doing their new tool to find people on maps.
But while I'm grateful they're doing it, I think it's a bit too OP. It's passive AF, and while you will certainly be able to disable it in the settings, there isn't much to use in-between. That's why I think a Ping feature could be useful, as much as some of the other possibilities CannedRat has proposed, because it's something you need to play. It's not automatic. CannedRat's ideas are more RP, pings have a cost (on pvp/factions servers).
@duh7you seems to mainly fear PZ being more casual and accessible. It's a valid fear but I don't think the devs are going in this direction. They'd have done another game if that was the case. Their own tool will be optional AFAIK, as would be the feature I propose. And perhaps it's not realistic, but realism is not the objective. Realism is a tool, and it shouldn't prevent people from having fun. Also, perhaps you don't realise it but the tone of your answers is condescending and it undermines your valid points.