Generally, it's not dangerous for your presets to update your instrument. Nevertheless, it's good practice to keep a backup of your sounds just in case something goes wrong.
For Mac, you can get SysEx Librarian:
https://www.snoize.com/SysExLibrarian/You can connect your Mac to your Prophet-6 via USB. Just make sure to set the global parameter "MIDI SysEx" to USB so that your instrument will receive and transmit your sounds using the USB port.
After you started SysEx Librarian, make sure that it will receive data from your Prophet-6. Simply choose the instrument from the drop down list at the top. Then press "record many," which puts the SysEx Librarian in waiting mode (it waits for receiving data, i.e. your programs). On the Prophet-6 you then go to the global parameter "Pgm Dump" and select the option that's suitable: Prg, Ten, Ban, usr, All(Program, Tens, Bank, User Banks, All). I guess the options "user banks" or "all" might be the most convenient in your case. After that, you just press the blinking Write button and whatever you selected will be transmitted to your Mac. The dumped programs will load back into the same bank and program locations when received by the Prophet-6 via MIDI again.