I understand by default geoclue use the available sources. In my case with my desktop PC, this is the geo-ip source. Then the accuracy is a city level accuracy. It's very bad. Today many services demands your exact position to give you for example the restaurants nearby you and not the restaurants of a whole city. I enabled the WI-FI source Google by adding a google key. Now the error is about a few hundred meters. I can discover the restaurants in my neighborhood. Good.