I have a large number of shots on my 128 GB card. When I do a Wi-Fi transfer, only the last few show up. The rest show on the camera but don’t show up when transferring.
It takes far longer to send by WiFi (or BlueTooth) than just popping the card into a laptop or reader. From even a quarter-filled 128 GB card, it likely takes so long that the camera shuts down to save the battery before the job finishes. Even the "blazingly fast" CamFi protocol is limited to 10Mbps, whereas a UHS-III card can be read at 312 MB/s.
If the transfer starts at the end and works backwards, you'd only get the last few files. So transfer continually, or limit the number of files by deleting old ones, if you must use WiFi, and cannot read the card directly.