Pretty cool, but I actually prefer the standard style in matplotlib.
I agree – it's interesting how one is initially drawn to, yet eventually tires of these sorts of plot styles. While Seaborn strikes a good balance, clear and simple monochrome plots never go out of fashion. This is just as much the case when building fancy interactive plots using Shiny/Plotly etc.
Monochrome is problematic for plots with multiple series though, because people's eyes aren't good at distinguishing shades of gray. You can use dashed lines for stuff like line plots, but those don't work well for complex trends and you can only use one or two.
I think monochrome is great for some uses, but at least for the area I work in the majority of figures use color. I'd say the main reason to use monochrome is for print, but most scientific journals are online nowadays and even conference proceedings are handed out in color. Now that doesn't mean everybody uses color well but that's a different discussion...