Aero road bikes have been around for a while now. They had a little dip in popularity, but for 2019 they are back with a vengeance. Many of the big name companies are busy updating their aero frames or some, such as Cervelo, are entirely overhauling their aero bike range.
As you ramp up your speed on a bike, more and more of your power is used to overcome aerodynamic drag. That may seem to be an obvious statement, but if you are a slower rider, you can still make big savings by going aero. In fact, your gains may even be bigger than those of the fast riders. So aero might be good for Peter Sagan, but it could be great for us mere mortals.