Not caught up, so someone else may have already said this. Efficiency does matter in this context. The "mph range per hour" charge rate that is displayed is a function of the charge power. Basically (voltage*amps)/(rated Wh/mile). The key being that the rated Wh/mile is based on the efficiency of the vehicle. The on-board AC charger is limited to the same peak power on all Teslas since ~2019, and it is FAR below the peak power accepted by any of the batteries. So improvements in batteries is not going to improve the AC charge rates in terms of watts. If you are trying to compare charge speeds of the batteries in different vehicles you can't go by mph/hour, you need to go by kWh/hour ie. watts. The refresh X isn't different than the previous X in that regard. Much older Xs are built with two on-board AC chargers, so they do have double the AC charge rate than the newer Xs (including refresh).
Supercharging (ie. DC charging) is different in that it bypasses the on-board AC charger and supplies power directly to the battery. This allows it to hit the max charge rate of the battery itself, and can vary depending on the battery in the vehicle.