SD card wear-levelling is usually supposed to be handled on the controller inside the SD card. SD cards aren't like having raw access to flash, you basically write over SPI and the controller in the SD card decides where to actually put it.
This talk about SD cards is really great and explains some of this:
This talk about SD cards is really great and explains some of this:
https://youtu.be/r3GDPwIuRKI?t=197