Fenix 5x Plus Depth Setting Question

So I’ve been flirting with the idea of getting the 5x Plus since they were on sale and I decided to pull the trigger yesterday. I have a Descent MK1 but the lack of updates/support for even the most basic things like a native Sunrise/Sunset, Alt Time zones widgets, Galileo, etc (all things that have been on other watches in this field for 5-6 months) have greatly frustrated me turned me in a different direction. Not a big fan of CIQ widgets/apps.

That said, while going through the settings (settings/system/units/depth) I came upon the option to choose feet or meters. I know there is a DiveIQ app out there, so was this feature added in for that or something else? I know there is a difference between air pressure and water pressure, so this is a bit perplexing. The MK1 is rated EN13319 but that’s in relation to depth and temp accuracy, it’s still 100m rated like the other Fenix watches.

I couldn’t find anything related to this anywhere, so any help is appreciated.