Save ggplot map produces bad results after being saved to geoTIFF

I'd like to create a good representation of my ggplot in geoTIFF, but the results is not so good. I try to:

#Packages
library(rgdal)
library(raster)
library(tiff)
library(ggplot2)
library(ggspatial)
library(sf)

# Get data set - x any are the points
all.stands.predict<-read.csv("https://raw.githubusercontent.com/Leprechault/trash/main/prediction__bug_2021-03-18.csv")
all.stands.predict<-all.stands.predict[all.stands.predict[,3]=="VILA PALMA",] # Area selection

#Create a map
(sites <- st_as_sf(all.stands.predict, coords = c("x", "y"), 
                   crs = 4326, agr = "constant"))
gg <- ggplot() +
  geom_sf(data=sites, color="red") +
  annotation_north_arrow(location = "bl", which_north = "true", 
                         pad_x = unit(0.3, "in"), pad_y = unit(0.5, "in"),
                         style = north_arrow_fancy_orienteering) + #Add a north arrow
  annotation_scale(location = "bl", width_hint = 0.55) + #Add a scale bar
  xlab("Latitude") + ylab("Longitude") +
  coord_sf() +
  theme_bw() 


# I inspected the map created
plot(gg)

# Save the plot
ggsave(plot=gg, "gg.tiff", device = "tiff", dpi = 600)

# Create a StackedRaster object from the saved plot
stackedRaster <- stack("gg.tiff")

# Get the GeoSpatial Components
lat_long <- ggplot_build(gg)$layout$panel_params[[1]][c("x_range","y_range")] 

# Supply GeoSpatial  data to the StackedRaster 
extent(stackedRaster) <- c(lat_long$x_range,lat_long$y_range)
projection(stackedRaster) <- CRS("+proj=longlat +datum=WGS84")

# Create the GeoTiff
writeRaster(stackedRaster, "myGeoTiffgg.tif", options="PHOTOMETRIC=RGB", datatype="INT1U",overwrite=TRUE)

#GeoTIFF representation:
ggr_geotiff <- stack("myGeoTiffgg.tif")
image(ggr_geotiff)

I need a good resolution geoTIFF similar to my plot(gg) with the margins and all the elements present in my ggobject. Please, any ideas?