I get the same good behaviour : using a “data cable” ( 4 wires inside) instead of a “charging cable” ( only 2 wires) GPS is much better.
I guess this is because the phone limits it current consumption as it “thinks” that there is computer at the other end of the line.
Maybe a software fix would be that as soon as GPS is enabled, charging current should be limited (as it seems that charging circuitry at full load inside the phone disturbs the GPS receiver).