Here’s my take on this. The accuracy really depends on the underlying technology being used, which is why you’re seeing conflicting information.
On one end of the spectrum, you have services that use the phone’s own GPS. This is the most accurate method, capable of pinpointing a location within a few meters. It’s what most people think of for “real-time” tracking, but it generally requires a specific app to be active on the device.
On the other end, there’s cell tower triangulation. This method estimates a location based on the phone’s distance from nearby cell towers. In a city with many towers, it can be reasonably accurate (maybe within a city block), but in rural areas, the margin of error can be quite large, sometimes several kilometers. It provides a general vicinity rather than an exact address.