It's a backup in case you edit/delete/re-order the factory presets. Maybe you want to get it back to factory fresh before you sell it.
But also, the fractal guys every so often go in and update the factory presets because enough things in the firmware have changed meaning some of the effects/settings/etc in the factory presets might need to be tweaked to get them back to what they're trying to sound like
So if you're the sort of person that spends a lot of time playing with the factory presets, or uses the factory presets as starting points to copy and tweak from, you might want to update to the latest so you have a better starting point. If you mostly ignore the factory presets, regularly delete them for space for your own presets, or download preset packs and install those instead of the factory presets then you can probably ignore these updates entirely. That said, you might find some ideas in the factory presets if you do explore them from time to time. You can just download them and preview them 1 by 1 and only copy the ones you like onto your Axe. They world is your oyster, shuck it how you please.