I am working with the FacetGrid example presented here that results in the plot below. In my data set, there is quite a lot of plots, and it would be convenient
FacetGrid
Just add the following lines after your def label(): function. Although the plot doesn't look that good with the modification you want.
def label():
for ax in g.axes.flat: _ = plt.setp(ax.get_xticklabels(), visible=True)
Output