Will a deactivated SIM card continue to improve location accuracy?

Will a deactivated SIM card continue to improve location accuracy?

It doesn't matter because it's a moot point. The cellular location services improves the performance of your location tracking by augmenting the GPS data, but it cannot improve the accuracy.

• Improve GPS accuracy by disabling cellular data

If you were just going off of the location data provided by the carrier, it would be at best "broad stroke" in terms of accuracy. Existing GPS is already accurate down to the cm (centimeter) range; how well your phone performs depends on the GPS chip that your phone uses. Roughly speaking, it'll give you accuracy within a couple of meters.