Stuck at NVIDIA logo and not booting

There might be something else wrong, but do beware that most of the boot content is not on the SD card…most (or all in recent releases) of the boot content is on the QSPI memory of the Nano itself. That software must be compatible in release version with the SD card’s content. The next step, even if this does turn out to be some other failure, would be to flash the Nano itself (which would update QSPI). Since your SD card is from JetPack 4.6, then you’d flash the non-working unit (not the SD card) with JetPack 4.6. After that it might just work with the 4.6 SD card.