Create an R spatial object rather than a gg object to enhance mapping capacity

[trashbirdecology]

Please correct me if I am wrong here, but the only spatial features I see in the maps are to obtain the CRS, and transform the object to a data frame (but not an SPDF). I see there is an option to snap other data frames having the same CRS to the usmap (gg).

Is there a simple way to back-transform the gg object to an SPDF or other spatial format outside gg universe?